We hit an assertion when loading the binary from PR 26813. When fixing
it, execution goes a up bit further but then hits another assert, and
another, and another. With these fours fixes, I am able to load the
binary and get to the prompt. An error is shown (index pointing outside
of the section), because the DW_FORM_rnglistx attribute is not read
correctly, but that one is taken care of by the next patch.
The four fixes are:
- attribute::form_requires_reprocessing needs to handle forms
DW_FORM_rnglistx and DW_FORM_loclistx, because set_unsigned_reprocess
is called for them in read_attribute_value.
- read_attribute_reprocess must call set_unsigned for them, not
set_address. The parameter of set_address is a CORE_ADDR, meaning
it's for program addresses. Post-reprocess, DW_FORM_rnglistx and
DW_FORM_loclistx are offsets into their respective sections
(.debug_rnglists and .debug_loclists). set_unsigned is the current
attribute value setter that fits the best. But perhaps we should have
a setter that takes a sect_offset?
- read_attribute_process must call as_unsigned_reprocess instead of
as_unsigned to get the pre-reprocess value, otherwise we hit the
assert inside as_unsigned that makes sure the attribute doesn't need
reprocessing.
- attribute::set_unsigned needs to clear the requires_reprocessing flag,
otherwise it stays set when reprocessing DW_FORM_rnglistx and
DW_FORM_loclistx attributes.
There's another assert that we hit once the next patch is applied, but
since it's in the same vein as the changes in this patch, I included it
in this patch:
- attribute::form_is_unsigned must handle form DW_FORM_loclistx,
otherwise we hit the assert when trying to call set_unsigned for an
attribute of this form. DW_FORM_rnglistx is already handled.
gdb/ChangeLog:
PR gdb/26813
* dwarf2/attribute.h (struct attribute) <set_unsigned>: Clear
requires_reprocessing flag.
* dwarf2/attribute.c (attribute::form_is_unsigned): Handle
DW_FORM_loclistx.
(attribute::form_requires_reprocessing): Handle DW_FORM_rnglistx
and DW_FORM_loclistx.
* dwarf2/read.c (read_attribute_reprocess): Use set_unsigned
instead of set_address for DW_FORM_loclistx and
DW_FORM_rnglistx.
Change-Id: I06c156fa3913ca98e4e39085f4ef171645b4bc1e
In read_rnglist_index and read_loclist_index, we check that both the
start and end of the offset that we read from the offset table are
within the section. I think it's unecessary to do both: if the end of
the offset is within the section, then surely the start of the offset is
within it.
Remove the check for the start of the offset in both functions.
gdb/ChangeLog:
* dwarf2/read.c (read_loclist_index): Remove bound check for
start of offset.
(read_rnglist_index): Likewise.
Change-Id: I7b57ddf4f8a8a28971738f0e3f3af62108f9e19a
read_rnglist_index has a bound check to make sure that we don't go past
the end of the section while reading the offset, but read_loclist_index
doesn't. Add it to read_loclist_index.
gdb/ChangeLog:
* dwarf2/read.c (read_loclist_index): Add bound check for the end
of the offset.
Change-Id: Ic4b55c88860fdc3e007740949c78ec84cdb4da60
I think this check in read_rnglist_index is wrong:
/* Validate that reading won't go beyond the end of the section. */
if (start_offset + cu->header.offset_size > rnglist_base + section->size)
error (_("Reading DW_FORM_rnglistx index beyond end of"
".debug_rnglists section [in module %s]"),
objfile_name (objfile));
The addition `rnglist_base + section->size` doesn't make sense.
rnglist_base is an offset into `section`, so it doesn't make sense to
add it to `section`'s size. `start_offset` also is an offset into
`section`, so we should just compare it to just `section->size`.
gdb/ChangeLog:
* dwarf2/read.c (read_rnglist_index): Fix bound check.
Change-Id: If0ff7c73f4f80f79aac447518f4e8f131f2db8f2
Unlike read_rnglists_index, read_loclist_index uses complaints when it
detects an inconsistency (a DW_FORM_loclistx value without a
.debug_loclists section or an offset outside of the section). I really
think they should be errors, since there's no point in continuing if
this situation happens, we will likely segfault or read garbage.
gdb/ChangeLog:
* dwarf2/read.c (read_loclist_index): Change complaints into
errors.
Change-Id: Ic3a1cf6e682d47cb6e739dd76fd7ca5be2637e10
While looking into a failure in gdb.go/package.exp with gcc-11, I noticed that
gdb shows some complaints when loading the executable (also with gcc-10, where
the test-case passes):
...
$ gdb -batch -iex "set complaints 100" package.10 -ex start
During symbol reading: Attribute value is not a constant (DW_FORM_sec_offset)
Temporary breakpoint 1 at 0x402ae6: file gdb.go/package1.go, line 8.
During symbol reading: Attribute value is not a constant (DW_FORM_sec_offset)
During symbol reading: Invalid .debug_rnglists data (no base address)
...
Fix this by using as_unsigned () to read DW_AT_ranges in the partial DIE
reader, similar to how that is done in dwarf2_get_pc_bounds.
Tested on x86_64-linux.
gdb/ChangeLog:
2021-01-25 Bernd Edlinger <bernd.edlinger@hotmail.de>
Simon Marchi <simon.marchi@polymtl.ca>
Tom de Vries <tdevries@suse.de>
* dwarf2/read.c (partial_die_info::read): Use as_unsigned () for
DW_AT_ranges.
gdb/testsuite/ChangeLog:
2021-01-25 Tom de Vries <tdevries@suse.de>
* gdb.dwarf2/dw2-ranges-psym.exp (gdb_load_no_complaints): New proc.
* lib/gdb.exp: Use gdb_load_no_complaints.
A recent version of GCC changed how fixed-point types are described.
For example, a denominator in one test case now looks like:
GNU_denominator (exprloc)
[ 0] implicit_value: 16 byte block: 00 00 b8 9d 0d 69 55 a0 01 00 00 00 00 00 00 00
... the difference being that this now uses exprloc and emits a
DW_OP_implicit_value for the 16-byte block. (DWARF 5 still uses
DW_FORM_data16.)
This change was made here:
https://gcc.gnu.org/pipermail/gcc-patches/2020-December/560897.html
This patch updates gdb to handle this situation.
Note that, before GCC 11, this test would not give the same answer.
Earlier versions of GCC fell back to GNAT encodings for this case.
gdb/ChangeLog
2021-01-25 Tom Tromey <tromey@adacore.com>
* dwarf2/read.c (get_mpz): New function.
(get_dwarf2_rational_constant): Use it.
gdb/testsuite/ChangeLog
2021-01-25 Tom Tromey <tromey@adacore.com>
* gdb.ada/fixed_points.exp: Add regression test.
* gdb.ada/fixed_points/fixed_points.adb (FP5_Var): New variable.
* gdb.ada/fixed_points/pck.adb (Delta5, FP5_Type): New.
The symptom that leads to this is the crash described in PR 26828:
/home/simark/src/binutils-gdb/gdb/dwarf2/read.c:23478:25: runtime error: member access within null pointer of type 'struct dwarf2_cu'
The line of the crash is the following, in follow_die_offset:
if (target_cu != cu)
target_cu->ancestor = cu; <--- HERE
The line that assign nullptr to `target_cu` is the `per_objfile->get_cu`
call after having called maybe_queue_comp_unit:
/* If necessary, add it to the queue and load its DIEs. */
if (maybe_queue_comp_unit (cu, per_cu, per_objfile, cu->language))
load_full_comp_unit (per_cu, per_objfile, per_objfile->get_cu (per_cu),
false, cu->language);
target_cu = per_objfile->get_cu (per_cu); <--- HERE
Some background: there is an invariant, documented in
maybe_queue_comp_unit's doc, that if a CU is queued for expansion
(present in dwarf2_per_bfd::queue), then its DIEs are loaded in memory.
"its DIEs are loaded in memory" is a synonym for saying that a dwarf2_cu
object exists for this CU. Yet another way to say it is that
`per_objfile->get_cu (per_cu)` returns something not nullptr for that
CU.
The crash documented in PR 26828 triggers some hard-to-reproduce
sequence that ends up violating the invariant:
- dwarf2_fetch_die_type_sect_off gets called for a DIE in CU A
- The DIE in CU A requires some DIE in CU B
- follow_die_offset calls maybe_queue_comp_unit. maybe_queue_comp_unit
sees CU B is not queued and its DIEs are not loaded, so it enqueues it
and returns 1 to its caller - meaning "the DIEs are not loaded, you
should load them" - prompting follow_die_offset to load the DIEs by
calling load_full_comp_unit
- Note that CU B is enqueued by maybe_queue_comp_unit even if it has
already been expanded. It's a bit useless (and causes trouble, see
next patch), but that's how it works right now.
- Since we entered the dwarf2/read code through
dwarf2_fetch_die_type_sect_off, nothing processes the queue, so we
exit the dwarf2/read code with CU B still lingering in the queue.
- dwarf2_fetch_die_type_sect_off gets called for a DIE in CU A, again
- The DIE in CU A requires some DIE in CU B, again
- This time, maybe_queue_comp_unit sees that CU B is in the queue.
Because of the invariant that if a CU is in the queue, its DIEs are
loaded in the memory, it returns 0 to its caller, meaning "you don't
need to load the DIEs!".
- That happens to be true, so everything is fine for now.
- Time passes, some things call dwarf2_per_objfile::age_comp_units
enough so that CU B's age becomes past the dwarf_max_cache_age
threshold. age_comp_units proceeds to free CU B's DIEs. Remember
that CU B is still lingering in the queue (oops, the invariant just
got violated).
- dwarf2_fetch_die_type_sect_off gets called for a DIE in CU A, again
- The DIE in CU A requires some DIE in CU B, again
- maybe_queue_comp_unit sees that CU B is in the queue, so returns to
its caller "you don't need to load the DIEs!". However, we know at
this point this is false.
- follow_die_offset doesn't load the DIEs and tries to obtain the DIEs for
CU B:
target_cu = per_objfile->get_cu (per_cu);
But since they are not loaded, target_cu is nullptr, and we get the
crash mentioned above a few lines after that.
This patch adds an assertions in maybe_queue_comp_unit to verify the
invariant, to make sure it doesn't return a falsehood to its caller.
The current patch doesn't fix the issue (the next patch does), but it
makes it so we catch the problem earlier and get this assertion failure
instead of a segmentation fault:
/home/simark/src/binutils-gdb/gdb/dwarf2/read.c:9100: internal-error:
int maybe_queue_comp_unit(dwarf2_cu*, dwarf2_per_cu_data*, dwarf2_per_objfile*, language):
Assertion `per_objfile->get_cu (per_cu) != nullptr' failed.
gdb/ChangeLog:
PR gdb/26828
* dwarf2/read.c (maybe_queue_comp_unit): Add assertion.
Change-Id: I4e51bd7bd58773f9fadf480179cbc4bae61508fe
This patch adds some logging that helped me diagnose the problems fixed
later in this series. I'm thinking that if it helped me now, it could
help somebody else (or myself) in the future, so I might as well add
them for real.
They can happen quite frequently and be noisy, so I used
dwarf_read_debug_printf_v for them, which means they'll only print if
`set debug dwarf-read` is >= 2.
gdb/ChangeLog:
* dwarf2/read.c (follow_die_offset): Add logging.
(dwarf2_per_objfile::age_comp_units): Add logging.
Change-Id: I7483c0b05c37bc9710b9b5d40e272935bc010863
This commits the result of running gdb/copyright.py as per our Start
of New Year procedure...
gdb/ChangeLog
Update copyright year range in copyright header of all GDB files.
The function c_printchar is called from two places; it provides the
implementation of language_defn::printchar and it is called from
dwarf2_compute_name.
It would be nice to rename c_printchar as language_defn::printchar and
so avoid the trampoline.
To achieve this, instead of calling c_printchar directly from the
DWARF code, I lookup the C++ language object and call the printchar
member function.
In a later commit I can then rename c_printchar.
There should be no user visible changes after this commit.
gdb/ChangeLog:
* dwarf2/read.c (dwarf2_compute_name): Call methods on C++
language object instead of calling global functions directly.
To handle thick pointers with -fgnat-encodings=minimal, gdb will
rewrite the underlying array type to remove the bounds. However, if
the same DWARF type is used both for a thick pointer and for an
ordinary array, this will have the side effect of removing the bounds
from the array. This breaks the printing of objects of this type.
This patch fixes the problem by copying the array type, its range, and
its bounds.
gdb/ChangeLog
2020-12-14 Tom Tromey <tromey@adacore.com>
* dwarf2/read.c (rewrite_array_type): New function.
(quirk_ada_thick_pointer_struct): Use rewrite_array_type.
gdb/testsuite/ChangeLog
2020-12-14 Tom Tromey <tromey@adacore.com>
* gdb.dwarf2/ada-thick-pointer.exp: New file.
The same pattern happens often to define a "debug_printf" macro:
#define displaced_debug_printf(fmt, ...) \
do \
{ \
if (debug_displaced) \
debug_prefixed_printf ("displaced", __func__, fmt, ##__VA_ARGS__); \
} \
while (0)
Move this pattern behind a helper macro, debug_prefixed_printf_cond and
update the existing macros to use it.
gdb/ChangeLog:
* displaced-stepping.h (displaced_debug_printf): Use
debug_prefixed_printf_cond.
* dwarf2/read.c (dwarf_read_debug_printf): Likewise.
(dwarf_read_debug_printf_v): Likewise.
* infrun.h (infrun_debug_printf): Likewise.
* linux-nat.c (linux_nat_debug_printf): Likewise.
gdbsupport/ChangeLog:
* common-debug.h (debug_prefixed_printf_cond): New.
* event-loop.h (event_loop_debug_printf): Use
debug_prefixed_printf_cond.
Change-Id: I1ff48b98b8d1cc405d1c7e8da8ceadf4e3a17f99
In some cases, GNAT can emit 128-bit constants for fixed-point types.
This patch changes gdb to handle this scenario, by changing the
low-level rational-reading functions in dwarf2/read.c to work directly
with gdb_mpz values. (I'm not sure offhand if these 128-bit patches
have gone into upstream GCC yet -- but they will eventually, and
meanwhile I think it should be clear that this patch is otherwise
harmless.)
gdb/ChangeLog
2020-12-09 Tom Tromey <tromey@adacore.com>
* dwarf2/read.c (get_dwarf2_rational_constant): Change "numerator"
and "denominator" to gdb_mpz. Handle block forms.
(get_dwarf2_unsigned_rational_constant): Change "numerator" and
"denominator" to gdb_mpz.
(finish_fixed_point_type): Update.
(has_zero_over_zero_small_attribute): Update.
When Debian (and Ubuntu) builds its binaries, it (still) doesn't use
dwz's "--relative" option. This causes their debuginfo files to
carry a .gnu_debugaltlink section containing a full pathname to the
DWZ alt debug file, like this:
$ readelf -wk /usr/bin/cat
Contents of the .gnu_debugaltlink section:
Separate debug info file: /usr/lib/debug/.dwz/x86_64-linux-gnu/coreutils.debug
Build-ID (0x14 bytes):
ee 76 5d 71 97 37 ce 46 99 44 32 bb e8 a9 1a ef 99 96 88 db
Contents of the .gnu_debuglink section:
Separate debug info file: 06d3bee37b8c7e67b31cb2689cb351102ae73b.debug
CRC value: 0x53267655
This usually works OK, because most of the debuginfo files installed
via apt will be present in /usr/lib/debug anyway. However, imagine
the following scenario:
- You are using /usr/bin/cat, it crashes on you and generates a
corefile.
- You don't want/need to "apt install" the debuginfo file for
coreutils from the repositories. Instead, you already have the
debuginfo files in a separate directory (e.g., $HOME/dbgsym).
- You start GDB and "set debug-file-directory $HOME/dbgsym/usr/lib/debug".
You then get the following message:
$ gdb -ex 'set debug-file-directory ./dbgsym/usr/lib/debug' -ex 'file /bin/cat' -ex 'core-file ./cat.core'
GNU gdb (Ubuntu 10.1-0ubuntu1) 10.1
...
Reading symbols from /bin/cat...
Reading symbols from /home/sergio/gdb/dbgsym/usr/lib/debug/.build-id/bc/06d3bee37b8c7e67b31cb2689cb351102ae73b.debug...
could not find '.gnu_debugaltlink' file for /home/sergio/gdb/dbgsym/usr/lib/debug/.build-id/bc/06d3bee37b8c7e67b31cb2689cb351102ae73b.debug
This error happens because GDB is trying to locate the build-id
link (inside /home/sergio/gdb/dbgsym/usr/lib/debug/.build-id) for the
DWZ alt debug file, which doesn't exist. Arguably, this is a problem
with how dh_dwz works in Debian, and it's something I'm also planning
to tackle. But, back at the problem at hand.
Besides not being able to find the build-id link in the directory
mentioned above, GDB also tried to open the DWZ alt file using its
filename. The problem here is that, since we don't have the distro's
debuginfo installed, it can't find anything under /usr/lib/debug that
satisfies it.
It occurred to me that a good way to workaround this problem is to
actually try to locate the DWZ alt debug file inside the
debug-file-directories (that were likely provided by the user). So
this is what the proposed patch does.
The idea here is simple: get the filename extracted from the
.gnu_debugaltlink section, and manipulate it in order to replace the
initial part of the path (everything before "/.dwz/") by whatever
debug-file-directories the user might have provided.
I talked with Mark Wielaard and he agrees this is a sensible approach.
In fact, apparently this is something that eu-readelf also does.
I regtested this code, and no regressions were found.
2020-12-01 Sergio Durigan Junior <sergiodj@sergiodj.net>
* dwarf2/read.c (dwz_search_other_debugdirs): New function.
(dwarf2_get_dwz_file): Convert 'filename' to a
std::string. Use dwz_search_other_debugdirs to search for DWZ
files in the debug-file-directories provided by the user as well.
This is one step further towards the removal of all these macros.
gdb/ChangeLog:
* gdbtypes.h (struct type) <fixed_point_info, set_fixed_point_info>:
New methods.
(INIT_FIXED_POINT_SPECIFIC): Adjust.
(TYPE_FIXED_POINT_INFO): Delete macro.
(allocate_fixed_point_type_info): Change return type to void.
* gdbtypes.c (copy_type_recursive): Replace the use of
TYPE_FIXED_POINT_INFO by a call to the fixed_point_info method.
(fixed_point_scaling_factor): Likewise.
(allocate_fixed_point_type_info): Change return type to void.
Adjust implementation accordingly.
* dwarf2/read.c (finish_fixed_point_type): Replace the use of
TYPE_FIXED_POINT_INFO by a call to the fixed_point_info method.
When building on solaris (gcc farm machine gcc211), I get:
CXX dwarf2/read.o
/export/home/simark/src/binutils-gdb/gdb/dwarf2/read.c: In function 'void finish_fixed_point_type(type*, die_info*, dwarf2_cu*)':
/export/home/simark/src/binutils-gdb/gdb/dwarf2/read.c:18204:42: error: call of overloaded 'abs(LONGEST&)' is ambiguous
*num_or_denom = 1 << abs (scale_exp);
^
In file included from /usr/include/stdlib.h:11:0,
from ../gnulib/import/stdlib.h:36,
from /opt/csw/include/c++/5.5.0/cstdlib:72,
from /export/home/simark/src/binutils-gdb/gdb/../gdbsupport/common-defs.h:90,
from /export/home/simark/src/binutils-gdb/gdb/defs.h:28,
from /export/home/simark/src/binutils-gdb/gdb/dwarf2/read.c:31:
/opt/csw/lib/gcc/sparc-sun-solaris2.10/5.5.0/include-fixed/iso/stdlib_iso.h:163:16: note: candidate: long int std::abs(long int)
inline long abs(long _l) { return labs(_l); }
^
/opt/csw/lib/gcc/sparc-sun-solaris2.10/5.5.0/include-fixed/iso/stdlib_iso.h:117:12: note: candidate: int std::abs(int)
extern int abs(int);
^
I don't know why, but using std::abs instead of just abs fixes it.
gdb/ChangeLog:
* dwarf2/read.c (finish_fixed_point_type): Use std::abs instead
of abs.
Change-Id: I57b9098351f2a8b2d2f61e848b97f7b2dfe55908
This commit introduces a new kind of type, meant to describe
fixed-point types, using a new code added specifically for
this purpose (TYPE_CODE_FIXED_POINT).
It then adds handling of fixed-point base types in the DWARF reader.
And finally, as a first step, this commit adds support for printing
the value of fixed-point type objects.
Note that this commit has a known issue: Trying to print the value
of a fixed-point object with a format letter (e.g. "print /x NAME")
causes the wrong value to be printed because the scaling factor
is not applied. Since the fix for this issue is isolated, and
this is not a regression, the fix will be made in a pach of its own.
This is meant to simplify review and archeology.
Also, other functionalities related to fixed-point type handling
(ptype, arithmetics, etc), will be added piecemeal as well, for
the same reasons (faciliate reviews and archeology). Related to this,
the testcase gdb.ada/fixed_cmp.exp is adjusted to compile the test
program with -fgnat-encodings=all, so as to force the use of GNAT
encodings, rather than rely on the compiler's default to use them.
The intent is to enhance this testcase to also test the pure DWARF
approach using -fgnat-encodings=minimal as soon as the corresponding
suport gets added in. Thus, the modification to the testcase is made
in a way that it prepares this testcase to be tested in both modes.
gdb/ChangeLog:
* ada-valprint.c (ada_value_print_1): Add fixed-point type handling.
* dwarf2/read.c (get_dwarf2_rational_constant)
(get_dwarf2_unsigned_rational_constant, finish_fixed_point_type)
(has_zero_over_zero_small_attribute): New functions.
read_base_type, set_die_type): Add fixed-point type handling.
* gdb-gdb.py.in: Add fixed-point type handling.
* gdbtypes.c: #include "gmp-utils.h".
(create_range_type, set_type_code): Add fixed-point type handling.
(init_fixed_point_type): New function.
(is_integral_type, is_scalar_type): Add fixed-point type handling.
(print_fixed_point_type_info): New function.
(recursive_dump_type, copy_type_recursive): Add fixed-point type
handling.
(fixed_point_type_storage): New typedef.
(fixed_point_objfile_key): New static global.
(allocate_fixed_point_type_info, is_fixed_point_type): New functions.
(fixed_point_type_base_type, fixed_point_scaling_factor): New
functions.
* gdbtypes.h: #include "gmp-utils.h".
(enum type_code) <TYPE_SPECIFIC_FIXED_POINT>: New enum.
(union type_specific) <fixed_point_info>: New field.
(struct fixed_point_type_info): New struct.
(INIT_FIXED_POINT_SPECIFIC, TYPE_FIXED_POINT_INFO): New macros.
(init_fixed_point_type, is_fixed_point_type)
(fixed_point_type_base_type, fixed_point_scaling_factor)
(allocate_fixed_point_type_info): Add declarations.
* valprint.c (generic_val_print_fixed_point): New function.
(generic_value_print): Add fixed-point type handling.
* value.c (value_as_address, unpack_long): Add fixed-point type
handling.
gdb/testsuite/ChangeLog:
* gdb.ada/fixed_cmp.exp: Force compilation to use -fgnat-encodings=all.
* gdb.ada/fixed_points.exp: Add fixed-point variables printing tests.
* gdb.ada/fixed_points/pck.ads, gdb.ada/fixed_points/pck.adb:
New files.
* gdb.ada/fixed_points/fixed_points.adb: Add use of package Pck.
* gdb.dwarf2/dw2-fixed-point.c, gdb.dwarf2/dw2-fixed-point.exp:
New files.
It took me a while to understand why that would even compile: it looks
like we pass a type name as a pointer, that makes no sense. By looking
at the DWARF, I understood that the compiler actually interprets it as a
function declaration. So the statement was doing nothing, no
dwarf2_queue_guard was instantiated. Fix it by passing the right
variable name.
gdb/ChangeLog:
* dwarf2/read.c (dw2_do_instantiate_symtab): Fix call to
dwarf2_queue_guard.
Change-Id: I3a7bdead9e8c39f8342a471f10181b85b8f0d801
Add dwarf_read_debug_printf and dwarf_read_debug_printf_v macros and use
them throughout dwarf2/read.c. The second one is used for "verbose"
prints, when the value of "set debug dwarf-read" is >= 2.
gdb/ChangeLog:
* dwarf2/read.c (dwarf_read_debug_printf,
dwarf_read_debug_printf_v): New macros, use throughout the file.
Change-Id: I694da69da2e1f2caa4c27a421a975790636411e2
In a longer series that I am working on, I needed to remove the
objfile parameter from abbrev_table::read. It seemed to me that this
was a simple and relatively harmless patch, so I'm sending it now.
gdb/ChangeLog
2020-11-05 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_cutu_die_from_dwo)
(cutu_reader::cutu_reader, cutu_reader::cutu_reader)
(build_type_psymtabs_1): Update.
* dwarf2/abbrev.h (struct abbrev_table): Remove objfile
parameter.
* dwarf2/abbrev.c (abbrev_table::read): Remove objfile parameter.
Don't read section. Add assert.
With -fgnat-encodings=minimal, Gnat will emit DW_TAG_array_type that
has a name -- and this is the only time the name is emitted for the
type. (For comparison, in C a typedef would be emitted in this
situation.)
This patch changes gdb to recognize the name of an array type. This
is limited to Ada, to avoid any potential problems if some rogue DWARF
happens to name an array type in some other language, and to avoid
loading unnecessary partial DIEs.
gdb/ChangeLog
2020-11-04 Tom Tromey <tromey@adacore.com>
* dwarf2/read.c (add_partial_symbol, process_die):
Handle DW_TAG_array_type.
(is_type_tag_for_partial): Add "lang" parameter.
(load_partial_dies, new_symbol): Handle DW_TAG_array_type.
gdb/testsuite/ChangeLog
2020-11-04 Tom Tromey <tromey@adacore.com>
* gdb.ada/tick_length_array_enum_idx.exp: Add ptype test.
* gdb.ada/tick_length_array_enum_idx/foo_n207_004.adb
(PT_Full): New variable.
* gdb.ada/tick_length_array_enum_idx/pck.adb
(Full_PT): New type.
A DWARF array type may specify a stride. Currently, the DWARF reader
applies this stride to every dimension of an array. However, this
seems incorrect to me -- only the innermost array ought to use the
stride, while outer arrays should compute a stride based on the size
of the inner arrays. This patch arranges to apply the stride only to
the innermost array type. This fixes a bug noticed when running some
Ada tests with -fgnat-encodings=minimal.
gdb/ChangeLog
2020-11-04 Tom Tromey <tromey@adacore.com>
* dwarf2/read.c (read_array_type): Only apply stride to innermost
array.
gdb/testsuite/ChangeLog
2020-11-04 Tom Tromey <tromey@adacore.com>
* gdb.ada/enum_idx_packed.exp: Add test.
* gdb.ada/enum_idx_packed/foo.adb (Multi_Access):
New variable.
* gdb.ada/enum_idx_packed/pck.ads (Short)
(Multi_Dimension, Multi_Dimension_Access): New types.
When -fgnat-encodings=minimal, the compiler will avoid the special
GNAT-specific "encodings" format, and instead emit ordinary DWARF as
much as possible.
When emitting DWARF for thick pointers to arrays, the compiler emits
something like:
<1><11db>: Abbrev Number: 7 (DW_TAG_array_type)
<11dc> DW_AT_name : (indirect string, offset: 0x1bb8): string
<11e0> DW_AT_data_location: 2 byte block: 97 6
(DW_OP_push_object_address; DW_OP_deref)
<11e3> DW_AT_type : <0x1173>
<11e7> DW_AT_sibling : <0x1201>
<2><11eb>: Abbrev Number: 8 (DW_TAG_subrange_type)
<11ec> DW_AT_type : <0x1206>
<11f0> DW_AT_lower_bound : 6 byte block: 97 23 8 6 94 4
(DW_OP_push_object_address; DW_OP_plus_uconst: 8; DW_OP_deref;
DW_OP_deref_size: 4)
<11f7> DW_AT_upper_bound : 8 byte block: 97 23 8 6 23 4 94 4
(DW_OP_push_object_address; DW_OP_plus_uconst: 8; DW_OP_deref;
DW_OP_plus_uconst: 4; DW_OP_deref_size: 4)
If you read between the lines, the "array" is actually a structure
with two elements. One element is a pointer to the array data, and
the other structure describes the bounds of the array. However, the
compiler doesn't emit this explicitly, but instead hides it behind
these location expressions.
gdb can print such objects, but currently there is no way to construct
one. So, this patch adds some code to the DWARF reader to recognize
this construct, and then synthesize an array descriptor. This
descriptor is then handled by the existing Ada code.
Internally, we've modified GCC to emit the structure type explicitly
(we will of course be sending this upstream). In this case, the array
still has the DW_AT_data_location, though. This patch also modifies
gdb to ignore the data location in this case -- this is preferred
because the location only serves to confuse the Ada code that already
knows where to find the data. In the future I hope to move some of
this handling to the gdb core, so that Ada-specific hacks are not
needed; however I have not yet done this.
Because parallel types are not emitted with -fgnat-encodings=minimal,
some changes to the Ada code were also required.
The change ina ada-valprint.c was needed to avoid infinite recursion
when trying to print a constrained packed array. And, there didn't
seem to be any need for a recursive call here -- the value could
simply be returned instead.
Finally, gdb.ada/frame_arg_lang.exp no longer works in C mode, because
we drop back to the structure approach now. As mentioned earlier,
future work should probably fix this again; meanwhile, this doesn't
seem to be a big problem, because it is what is currently done (users
as a rule don't use -fgnat-encodings=minimal -- which is what I am
ultimately trying to fix).
Note that a couple of tests have an added KFAIL. Some
-fgnat-encodings=minimal changes have landed in GNAT, and you need
something very recent to pass all the tests. I'm using git gcc to
accomplish this.
gdb/ChangeLog
2020-11-04 Tom Tromey <tromey@adacore.com>
* dwarf2/read.c (recognize_bound_expression)
(quirk_ada_thick_pointer): New functions.
(read_array_type): Call quirk_ada_thick_pointer.
(set_die_type): Add "skip_data_location" parameter.
(quirk_ada_thick_pointer): New function.
(process_structure_scope): Call quirk_ada_thick_pointer.
* ada-lang.c (ada_is_unconstrained_packed_array_type)
(decode_packed_array_bitsize): Handle thick pointers without
parallel types.
(ada_is_gnat_encoded_packed_array_type): Rename from
ada_is_packed_array_type.
(ada_is_constrained_packed_array_type): Update.
* ada-valprint.c (ada_val_print_gnat_array): Remove.
(ada_value_print_1): Use ada_get_decoded_value.
gdb/testsuite/ChangeLog
2020-11-04 Tom Tromey <tromey@adacore.com>
* gdb.ada/O2_float_param.exp: Test different -fgnat-encodings
values.
* gdb.ada/access_to_unbounded_array.exp: Test different
-fgnat-encodings values.
* gdb.ada/big_packed_array.exp: Test different -fgnat-encodings
values.
* gdb.ada/arr_enum_idx_w_gap.exp: Test different -fgnat-encodings
values.
* gdb.ada/array_ptr_renaming.exp: Test different -fgnat-encodings
values.
* gdb.ada/array_of_variable_length.exp: Test different
-fgnat-encodings values.
* gdb.ada/arrayparam.exp: Test different -fgnat-encodings values.
* gdb.ada/arrayptr.exp: Test different -fgnat-encodings values.
* gdb.ada/frame_arg_lang.exp: Revert -fgnat-encodings=minimal
change.
* gdb.ada/mi_string_access.exp: Test different -fgnat-encodings
values.
* gdb.ada/mod_from_name.exp: Test different -fgnat-encodings values.
* gdb.ada/out_of_line_in_inlined.exp: Test different
-fgnat-encodings values.
* gdb.ada/packed_array.exp: Test different -fgnat-encodings
values.
* gdb.ada/pckd_arr_ren.exp: Test different -fgnat-encodings
values.
* gdb.ada/unc_arr_ptr_in_var_rec.exp: Test different
-fgnat-encodings values.
* gdb.ada/variant_record_packed_array.exp: Test different
-fgnat-encodings values.
This changes end_psymtab_common to be a method on partial_symtab.
This seems a little cleaner to me.
gdb/ChangeLog
2020-11-01 Tom Tromey <tom@tromey.com>
* dbxread.c (dbx_end_psymtab): Update.
* dwarf2/read.c (process_psymtab_comp_unit_reader)
(build_type_psymtabs_reader): Update.
* xcoffread.c (xcoff_end_psymtab): Update.
* ctfread.c (scan_partial_symbols): Update.
* psymtab.c (sort_pst_symbols): Remove.
(partial_symtab::end): Rename from end_psymtab_common. Inline
sort_pst_symbols.
* psympriv.h (struct partial_symtab) <end>: New method.
(end_psymtab_common): Don't declare.
init_psymbol_list is now empty, and so this removes it.
gdb/ChangeLog
2020-11-01 Tom Tromey <tom@tromey.com>
* dbxread.c (dbx_symfile_read): Update.
* dwarf2/read.c (dwarf2_build_psymtabs): Update.
* xcoffread.c (xcoff_initial_scan): Update.
* psympriv.h (init_psymbol_list): Don't declare.
* psymtab.c (init_psymbol_list): Remove.
Consider the test-case contained in this patch. It consists of
two CUs:
- cu1, containing a DW_TAG_variable DIE foo
- cu2, containing a DW_TAG_base_type DIE int
where the variable foo has type int, in other words, there's an inter-CU
reference.
When expanding the symtab for cu1, expansion of the symtab for cu2 is
enqueued, and later processed by process_full_comp_unit. However, processing
of .debug_ranges fails because the range is specified relative to a base
address which is considered not to be present because
!cu->base_address.has_value (), and we run into this case in
dwarf2_ranges_process:
...
if (!base.has_value ())
{
/* We have no valid base address for the ranges
data. */
complaint (_("Invalid .debug_ranges data (no base address)"));
return 0;
}
...
Fix this in process_full_comp_unit by setting cu->base_address.
Tested on x86_64-linux.
gdb/ChangeLog:
2020-10-26 Tom de Vries <tdevries@suse.de>
* dwarf2/read.c (process_full_comp_unit): Call
dwarf2_find_base_address.
gdb/testsuite/ChangeLog:
2020-10-26 Tom de Vries <tdevries@suse.de>
* gdb.dwarf2/enqueued-cu-base-addr.exp: New file.
Fix a regression introduced by commit 7188ed02d2 ("Replace
dwarf2_per_cu_data::cu backlink with per-objfile map").
This patch targets both master and gdb-10-branch, since this is a
regression from GDB 9.
Analysis
--------
The DWARF generated by the included test case looks like:
0x0000000b: DW_TAG_compile_unit
DW_AT_language [DW_FORM_sdata] (4)
0x0000000d: DW_TAG_base_type
DW_AT_name [DW_FORM_string] ("int")
DW_AT_byte_size [DW_FORM_data1] (0x04)
DW_AT_encoding [DW_FORM_sdata] (5)
0x00000014: DW_TAG_subprogram
DW_AT_name [DW_FORM_string] ("apply")
0x0000001b: DW_TAG_subprogram
DW_AT_specification [DW_FORM_ref4] (0x00000014 "apply")
DW_AT_low_pc [DW_FORM_addr] (0x0000000000001234)
DW_AT_high_pc [DW_FORM_data8] (0x0000000000000020)
0x00000030: DW_TAG_template_type_parameter
DW_AT_name [DW_FORM_string] ("T")
DW_AT_type [DW_FORM_ref4] (0x0000000d "int")
0x00000037: NULL
0x00000038: NULL
Simply loading the file in GDB makes it crash:
$ ./gdb -nx --data-directory=data-directory testsuite/outputs/gdb.dwarf2/pr26693/pr26693
[1] 15188 abort (core dumped) ./gdb -nx --data-directory=data-directory
The crash happens here, where htab (a dwarf2_cu::die_hash field) is
unexpectedly NULL while generating partial symbols:
#0 0x000055555fa28188 in htab_find_with_hash (htab=0x0, element=0x7fffffffbfa0, hash=27) at /home/simark/src/binutils-gdb/libiberty/hashtab.c:591
#1 0x000055555cb4eb2e in follow_die_offset (sect_off=(unknown: 27), offset_in_dwz=0, ref_cu=0x7fffffffc110) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:22951
#2 0x000055555cb4edfb in follow_die_ref (src_die=0x0, attr=0x7fffffffc130, ref_cu=0x7fffffffc110) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:22968
#3 0x000055555caa48c5 in partial_die_full_name (pdi=0x621000157e70, cu=0x615000023f80) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:8441
#4 0x000055555caa4d79 in add_partial_symbol (pdi=0x621000157e70, cu=0x615000023f80) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:8469
#5 0x000055555caa7d8c in add_partial_subprogram (pdi=0x621000157e70, lowpc=0x7fffffffc5c0, highpc=0x7fffffffc5e0, set_addrmap=1, cu=0x615000023f80) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:8737
#6 0x000055555caa265c in scan_partial_symbols (first_die=0x621000157e00, lowpc=0x7fffffffc5c0, highpc=0x7fffffffc5e0, set_addrmap=1, cu=0x615000023f80) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:8230
#7 0x000055555ca98e3f in process_psymtab_comp_unit_reader (reader=0x7fffffffc6b0, info_ptr=0x60600009650d "\003int", comp_unit_die=0x621000157d10, pretend_language=language_minimal) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:7614
#8 0x000055555ca9aa2c in process_psymtab_comp_unit (this_cu=0x621000155510, per_objfile=0x613000009f80, want_partial_unit=false, pretend_language=language_minimal) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:7712
#9 0x000055555caa051a in dwarf2_build_psymtabs_hard (per_objfile=0x613000009f80) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:8073
The special thing about this DWARF is that the subprogram at 0x1b is a
template specialization described with DW_AT_specification, and has no
DW_AT_name in itself. To compute the name of this subprogram,
partial_die_full_name needs to load the full DIE for this partial DIE.
The name is generated from the templated function name and the actual
tempalate parameter values of the specialization.
To load the full DIE, partial_die_full_name creates a dummy DWARF
attribute of form DW_FORM_ref_addr that points to our subprogram's DIE,
and calls follow_die_ref on it. This eventually causes
load_full_comp_unit to be called for the exact same CU we are currently
making partial symbols for:
#0 load_full_comp_unit (this_cu=0x621000155510, per_objfile=0x613000009f80, skip_partial=false, pretend_language=language_minimal) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:9238
#1 0x000055555cb4e943 in follow_die_offset (sect_off=(unknown: 27), offset_in_dwz=0, ref_cu=0x7fffffffc110) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:22942
#2 0x000055555cb4edfb in follow_die_ref (src_die=0x0, attr=0x7fffffffc130, ref_cu=0x7fffffffc110) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:22968
#3 0x000055555caa48c5 in partial_die_full_name (pdi=0x621000157e70, cu=0x615000023f80) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:8441
#4 0x000055555caa4d79 in add_partial_symbol (pdi=0x621000157e70, cu=0x615000023f80) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:8469
#5 0x000055555caa7d8c in add_partial_subprogram (pdi=0x621000157e70, lowpc=0x7fffffffc5c0, highpc=0x7fffffffc5e0, set_addrmap=1, cu=0x615000023f80) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:8737
#6 0x000055555caa265c in scan_partial_symbols (first_die=0x621000157e00, lowpc=0x7fffffffc5c0, highpc=0x7fffffffc5e0, set_addrmap=1, cu=0x615000023f80) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:8230
#7 0x000055555ca98e3f in process_psymtab_comp_unit_reader (reader=0x7fffffffc6b0, info_ptr=0x60600009650d "\003int", comp_unit_die=0x621000157d10, pretend_language=language_minimal) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:7614
#8 0x000055555ca9aa2c in process_psymtab_comp_unit (this_cu=0x621000155510, per_objfile=0x613000009f80, want_partial_unit=false, pretend_language=language_minimal) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:7712
#9 0x000055555caa051a in dwarf2_build_psymtabs_hard (per_objfile=0x613000009f80) at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:8073
load_full_comp_unit creates a cutu_reader for the CU. Since a dwarf2_cu
object already exists for the CU, load_full_comp_unit is expected to
find it and pass it to cutu_reader, so that cutu_reader doesn't create
a new dwarf2_cu for the CU.
And this is the difference between before and after the regression.
Before commit 7188ed02d2, the dwarf2_per_cu_data -> dwarf2_cu link was
a simple pointer in dwarf2_per_cu_data. This pointer was set up when
starting the read the partial symbols. So it was already available at
that point where load_full_comp_unit gets called. Post-7188ed02d2a7,
this link is per-objfile, kept in the dwarf2_per_objfile::m_dwarf2_cus
hash map. The entry is only put in the hash map once the partial
symbols have been successfully read, when cutu_reader::keep is called.
Therefore, it is _not_ set at the point load_full_comp_unit is called.
As a consequence, a new dwarf2_cu object gets created and initialized by
load_full_comp_unit (including initializing that dwarf2_cu::die_hash
field). Meanwhile, the dwarf2_cu object created and used by the callers
up the stack does not get initialized for full symbol reading, and the
dwarf2_cu::die_hash field stays unexpectedly NULL.
Solution
--------
Since the caller of load_full_comp_unit knows about the existing
dwarf2_cu object for the CU we are reading (the one load_full_comp_unit
is expected to find), we can simply make it pass it down, instead of
having load_full_comp_unit look up the per-objfile map.
load_full_comp_unit therefore gets a new `existing_cu` parameter. All
other callers get updated to pass `per_objfile->get_cu (per_cu)`, so the
behavior shouldn't change for them, compared to the current HEAD.
A test is added, which is the bare minimum to reproduce the issue.
Notes
-----
The original problem was reproduced by downloading
https://github.com/oneapi-src/oneTBB/releases/download/v2020.3/tbb-2020.3-lin.tgz
and loading libtbb.so in GDB. This code was compiled with the Intel
C/C++ compiler. I was not able to reproduce the issue using GCC, I
think because GCC puts a DW_AT_name in the specialized subprogram, so
there's no need for partial_die_full_name to load the full DIE of the
subprogram, and the faulty code doesn't execute.
gdb/ChangeLog:
PR gdb/26693
* dwarf2/read.c (load_full_comp_unit): Add existing_cu
parameter.
(load_cu): Pass existing CU.
(process_imported_unit_die): Likewise.
(follow_die_offset): Likewise.
gdb/testsuite/ChangeLog:
PR gdb/26693
* gdb.dwarf2/template-specification-full-name.exp: New test.
Change-Id: I57c8042f96c45f15797a3848e4d384181c56bb44
Currently pointers to all partial symbols are stored in two vectors;
and then indices into these vectors are stored in each partial_symtab.
This patch changes this so that each partial symtab instead has
vectors of symbols. add_psymbol_to_list can now be changed into a
method on partial_symtab as well.
My main motivation for doing this is that I am looking into calling
sort_pst_symbols in the background. However, I haven't actually
implemented this yet. (Also this may make it more feasible to also
sort the static psymbols, though I haven't tried that either.)
Also, though, this lets us remove the "current_global_psymbols"
vector, because now the callers can simply refer directly to the
psymtab that they are modifying (formerly this was implicit).
The main drawback of this patch is that it increases the size of
partial symtab.
gdb/ChangeLog
2020-10-17 Tom Tromey <tom@tromey.com>
* xcoffread.c (xcoff_end_psymtab): Use partial_symtab::empty.
(scan_xcoff_symtab): Update.
* psymtab.h (class psymtab_storage) <global_psymbols,
static_psymbols, current_global_psymbols,
current_static_psymbols>: Remove.
* psymtab.c (require_partial_symbols, find_pc_sect_psymbol)
(match_partial_symbol, lookup_partial_symbol): Update.
(print_partial_symbols): Change parameters.
(dump_psymtab, recursively_search_psymtabs)
(psym_fill_psymbol_map, psym_find_compunit_symtab_by_address)
(sort_pst_symbols, partial_symtab::partial_symtab): Update.
(concat): Remove.
(end_psymtab_common): Simplify.
(append_psymbol_to_list): Change parameters.
(partial_symtabs::add_psymbol): Rename from add_psymbol_to_list.
(init_psymbol_list): Simplify.
(maintenance_info_psymtabs, maintenance_check_psymtabs): Update.
* psympriv.h (struct partial_symtab) <empty>: New method.
<globals_offset, n_global_syms, statics_offset, n_static_syms>:
Remove.
<global_psymbols, static_psymbols>: New members.
<add_psymbol>: New methods.
(add_psymbol_to_list): Don't declare.
(psymbol_placement): Move earlier.
* mdebugread.c (parse_partial_symbols): Update.
(handle_psymbol_enumerators): Change parameters.
(mdebug_expand_psymtab): Update.
* dwarf2/read.c (process_psymtab_comp_unit_reader)
(add_partial_symbol): Update.
* dwarf2/index-write.c (write_psymbols): Change parameters.
(write_one_signatured_type): Update.
(recursively_count_psymbols): Update.
(recursively_write_psymbols): Update.
(class debug_names) <recursively_write_psymbols>: Update.
<write_psymbols>: Change parameters.
<write_one_signatured_type>: Update.
* dbxread.c (read_dbx_symtab): Update.
(dbx_end_psymtab): Use partial_symtab::empty.
* ctfread.c (struct ctf_context) <pst>: New member.
(create_partial_symtab): Set it.
(ctf_psymtab_type_cb, ctf_psymtab_var_cb): Update.
(scan_partial_symbols): Use the psymtab's context. Update.
The type-safe attribute patch introduced a regression that can occur
when the DW_AT_bit_offset value is negative. This can happen with
some Ada programs.
This patch fixes the problem. It also fixes a minor oddity in the
existing scalar storage test -- this test was intended to assign a
smaller number of bits to the field.
2020-10-09 Tom Tromey <tromey@adacore.com>
* dwarf2/read.c (dwarf2_add_field): Handle signed offsets.
gdb/testsuite/ChangeLog
2020-10-09 Tom Tromey <tromey@adacore.com>
* gdb.ada/scalar_storage/storage.adb (Another_Range): New type.
(Rec): Add field. Fix range.
* gdb.ada/scalar_storage.exp: Update.
GDB complaints "During symbol reading: unrecognized DW_MACFINO
opcode 0xb" with the testcase given below. Clang is emitting
DW_MACRO_define_strx and DW_MACRO_undef_strx entries in .debug_macro
section which are not supported in GDB. This patch handles them.
DW_MACRO_define_strx and DW_MACRO_undef_strx are added in DWARFv5.
They have two operands. The first operand encodes the line number of
the #define or #undef macro directive. The second operand identifies
a string; it is represented using an unsigned LEB128 encoded value,
which is interpreted as a zero-based index into an array of offsets
in the .debug_str_offsets section. This is as per the section 6.3.2.1
of Dwarf Debugging Information Format Version 5.
Test case used:
#define MAX_SIZE 10
int main(void)
{
int size = 0;
size = size + MAX_SIZE;
printf("\n The value of size is [%d]\n",size);
return 0;
}
clang -gdwarf-5 -fdebug-macro macro.c -o macro.out
Before the patch:
gdb/new_gdb/binutils-gdb/build/bin/gdb -q macro.out -ex "set complaints 1" -ex "start"
Reading symbols from macro.out...
During symbol reading: unrecognized DW_MACFINO opcode 0xb
Temporary breakpoint 1 at 0x4004df: file macro.c, line 7.
Starting program: /home/nitika/workspace/macro.out
Temporary breakpoint 1, main () at macro.c:7
7 int size = 0;
(gdb)
Tested by running the testsuite before and after the patch with
-gdwarf-5 and there is no increase in the number of test cases
that fails. Used clang 11.0.0.
gdb/ChangeLog:
* dwarf2/macro.c (dwarf_decode_macro_bytes): Handle DW_MACRO_define_strx
and DW_MACRO_undef_strx.
(dwarf_decode_macros): Likewise
* dwarf2/read.c (dwarf_decode_macros): Pass str_offsets_base in the parameters
which is the value of DW_AT_str_offsets_base.
* dwarf2/macro.h (dwarf_decode_macros): Modify the definition to include
str_offsets_base.
Since commit 2c830f5475 "Change some uses of DW_STRING to string method" we
have these regressions:
...
FAIL: gdb.base/info-types-c++.exp: info types
FAIL: gdb.cp/anon-struct.exp: print type of t::t
FAIL: gdb.cp/anon-struct.exp: print type of X::t2
FAIL: gdb.cp/anon-struct.exp: print type of X::t2::t2
FAIL: gdb.cp/anon-struct.exp: print type of t3::~t3
...
Fix these in dwarf2_name by updating attr_name each time attr is updated.
Tested on x86_64-linux.
gdb/ChangeLog:
2020-09-30 Tom de Vries <tdevries@suse.de>
PR symtab/26683
* dwarf2/read.c (dwarf2_name): Update attr_name after attr is updated.
My series to change DWARF attribute handling to be type-safe
introduced a regression in gdb.ada/variant.exp. handle_variant was
using as_unsigned on an attribute with DW_FORM_sdata. This patch
changes it to use constant_value instead.
2020-09-30 Tom Tromey <tromey@adacore.com>
* dwarf2/read.c (handle_variant): Use constant_value.
This removes DW_UNSND, replacing uses with either as_unsigned or
constant_value, depending primarily on whether or not the form is
already known to be appropriate.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (lookup_dwo_id, get_type_unit_group)
(read_file_scope, dwarf2_get_pc_bounds)
(dwarf2_record_block_ranges, dwarf2_add_field, get_alignment)
(read_structure_type, handle_struct_member_die)
(read_enumeration_type, read_array_type, read_set_type)
(read_tag_pointer_type, read_tag_reference_type)
(read_subroutine_type, read_base_type, read_subrange_type)
(read_full_die_1, partial_die_info::read)
(partial_die_info::read, by, new_symbol)
(dwarf2_const_value_data, dwarf2_const_value_attr)
(dump_die_shallow, dwarf2_fetch_constant_bytes)
(prepare_one_comp_unit): Update.
* dwarf2/attribute.h (DW_UNSND): Remove.
This adds a new attribute::as_boolean method, and updates the reader
to use it. The main benefit of this change is that now the code will
respect the attribute's form.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_func_scope, prototyped_function_p)
(read_subroutine_type, partial_die_info::read)
(dwarf2_flag_true_p, new_symbol, dump_die_shallow)
(dwarf2_add_member_fn): Update.
* dwarf2/attribute.h (struct attribute) <as_boolean>: Declare.
* dwarf2/attribute.c (attribute::as_boolean): New method.
This adds a new attribute::as_virtuality method and changes the DWARF
reader to use it. This also ensures that the attibute's form will now
be respected.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (dwarf2_add_field, dwarf2_add_member_fn): Update.
* dwarf2/attribute.h (struct attribute) <as_virtuality>: New
method.
* dwarf2/attribute.c (attribute::as_virtuality): New method.
This changes is_valid_DW_AT_defaulted to be a method on struct attribute.
Now it correctly respects the form of the attribute.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (is_valid_DW_AT_defaulted): Move to attribute.c.
(dwarf2_add_member_fn): Update.
* dwarf2/attribute.h (struct attribute) <defaulted>: Declare.
* dwarf2/attribute.c (attribute::defaulted): New method, from
is_valid_DW_AT_defaulted.
This introduces a new attribute::as_unsigned method and changes a few
spots to use it.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (dw2_get_file_names_reader)
(dwarf2_build_include_psymtabs, handle_DW_AT_stmt_list)
(dwarf2_cu::setup_type_unit_groups, fill_in_loclist_baton)
(dwarf2_symbol_mark_computed): Use as_unsigned.
* dwarf2/attribute.h (struct attribute) <as_unsigned>: New
method.
<form_is_section_offset>: Update comment.
dwarf2/read.c uses dwarf2_default_access_attribute to check for the
default access attribute. This patch simplifies the code by moving
more of the access processing into this function, changing its name to
reflect the difference. This also ensures that the attribute's form
is respected, by changing to code to use the constant_value method.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (dwarf2_access_attribute): Rename from
dwarf2_default_access_attribute. Look up attribute.
(dwarf2_add_field, dwarf2_add_type_defn, dwarf2_add_member_fn):
Update.
Currently gdb keeps a vector of attributes that require reprocessing.
However, now that there is a reprocessing flag in the attribute, we
can remove the vector and instead simply loop over attributes a second
time. Normally there are not many attributes, so this should be
reasonably cheap.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (skip_one_die): Update.
(read_full_die_1): Change how reprocessing is done.
(partial_die_info::read): Update.
(read_attribute_value): Remove need_reprocess parameter.
(read_attribute): Likewise.
* dwarf2/attribute.h (struct attribute) <requires_reprocessing_p>:
New method.
Some forms require "reprocessing" -- a second pass to update their
value appropriately. In this case, we'll set the unsigned value on
the attribute, and then later set it to the correct value.
To handle this, we introduce a reprocessing flag to attribute. Then,
we manage this flag to ensure that setting and unsetting is done
properly.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_cutu_die_from_dwo): Use OBSTACK_ZALLOC.
(read_attribute_reprocess, read_attribute_value): Update.
(read_attribute): Clear requires_reprocessing.
* dwarf2/attribute.h (struct attribute) <as_unsigned_reprocess,
form_requires_reprocessing>: New methods.
<string_init>: Clear requires_reprocessing.
<set_unsigned_reprocess>: New method.
<name>: Shrink by one bit.
<requires_reprocessing>: New member.
* dwarf2/attribute.c (attribute::form_requires_reprocessing): New
method.
This adds form_is_unsigned and an unsigned setter method to struct
attribute, and updates the remaining code. Now DW_UNSND is no longer
used as an lvalue.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_attribute_value): Update.
* dwarf2/attribute.h (struct attribute) <form_is_unsigned,
set_unsigned>: New methods.
* dwarf2/attribute.c (attribute::form_is_unsigned): New method.
This removes DW_SND in favor of accessors on struct attribute.
These accessors check that the form is appropriate.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (get_alignment, read_array_order)
(read_attribute_value, dwarf2_const_value_attr)
(dump_die_shallow, dwarf2_fetch_constant_bytes): Update.
* dwarf2/attribute.h (struct attribute) <as_signed, set_signed>:
New methods.
(DW_SND): Remove.
This removes DW_SIGNATURE in favor of methods on struct attribute. As
usual, the methods check the form, which DW_SIGNATURE did not do.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_attribute_value, lookup_die_type)
(dump_die_shallow, follow_die_sig, get_DW_AT_signature_type):
Update.
* dwarf2/attribute.h (struct attribute) <as_signature,
set_signature>: New methods.
(DW_SIGNATURE): Remove.
This removes the DW_BLOCK accessor in favor of methods on struct
attribute. The methods, unlike the access, check the form.
Note that DW_FORM_data16 had to be handled by form_is_block, because
in practice that is how we store values of this form.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_call_site_scope)
(handle_data_member_location, dwarf2_add_member_fn)
(mark_common_block_symbol_computed, attr_to_dynamic_prop)
(partial_die_info::read, read_attribute_value)
(var_decode_location, dwarf2_const_value_attr, dump_die_shallow)
(dwarf2_fetch_die_loc_sect_off, dwarf2_fetch_constant_bytes)
(dwarf2_symbol_mark_computed): Update.
* dwarf2/attribute.h (struct attribute) <as_block, set_block>: New
methods.
(DW_BLOCK): Remove.
* dwarf2/attribute.c (attribute::form_is_block): Add
DW_FORM_data16.
This removes DW_STRING and DW_STRING_IS_CANONICAL, replacing them with
accessor methods on struct attribute. The new code ensures that a
string value will only ever be used when the form allows it.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (read_cutu_die_from_dwo)
(read_attribute_reprocess, read_attribute_value, read_attribute)
(dwarf2_const_value_attr, dwarf2_name, dump_die_shallow)
(dwarf2_fetch_constant_bytes): Update.
* dwarf2/attribute.h (struct attribute) <form_is_string>: Declare.
<set_string_noncanonical, set_string_canonical>: New methods.
<string_is_canonical>: Update comment.
<canonical_string_p>: Add assert.
(DW_STRING, DW_STRING_IS_CANONICAL): Remove.
* dwarf2/attribute.c (attribute::form_is_string): New method.
(attribute::string): Use it.
This removes the rvalue uses of DW_STRING_IS_CANONICAL, replacing them
with an accessor method.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (anonymous_struct_prefix, dwarf2_name)
(dump_die_shallow): Use canonical_string_p.
* dwarf2/attribute.h (struct attribute) <canonical_string_p>: New
method.
This changes some of the simpler spots to use attribute::string rather
than DW_STRING.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (partial_die_info::read)
(dwarf2_const_value_attr, anonymous_struct_prefix, )
(dwarf2_name, dwarf2_fetch_constant_bytes): Use
attribute::as_string.
This removes the "value_" prefix from the struct value accessors.
This seemed unnecessarily wordy to me.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (dwarf2_find_base_address, read_call_site_scope)
(dwarf2_get_pc_bounds, dwarf2_record_block_ranges)
(partial_die_info::read, dwarf2_string_attr, new_symbol): Update.
* dwarf2/attribute.h (struct attribute): Rename methods.
* dwarf2/attribute.c (attribute::as_address): Rename from
value_as_address.
(attribute::as_string): Rename from value_as_string.
The full DIE reader checks that an attribute has a "string" form in
some spots, but the partial DIE reader does not. This patch brings
the two readers in sync for one specific case, namely when examining
the linkage name. This avoids regressions in an existing DWARF test
case.
A full fix for this problem would be preferable. An accessor like
DW_STRING should always check the form. However, I haven't attempted
that in this series.
Also the fact that the partial and full readers can disagree like this
is a design flaw.
gdb/ChangeLog
2020-09-29 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (partial_die_info::read) <case
DW_AT_linkage_name>: Use value_as_string.
(dwarf2_string_attr): Use value_as_string.
* dwarf2/attribute.h (struct attribute) <value_as_string>: Declare
method.
* dwarf2/attribute.c (attribute::value_as_string): New method.
PR symtab/25470 points out that the Zig programming language allows
integers of various bit sizes (including zero), not just sizes that
are a multiple of 8.
This is supported in DWARF by applying both a byte size and a
DW_AT_bit_size.
This patch adds support for this feature to integer and boolean types.
Other base types are not handled -- for floating-point types, this
didn't seem to make sense, and for character types I didn't see much
need. (These can be added later if desired.)
I've also added support for DW_AT_data_bit_offset at the same time. I
don't know whether the Zig compiler requires this, but it was
described in the same section in the DWARF standard and was easy to
add.
A new test case is supplied, using the DWARF assembler.
gdb/ChangeLog
2020-09-23 Tom Tromey <tom@tromey.com>
PR symtab/25470:
* value.c (unpack_long, pack_long, pack_unsigned_long): Handle bit
offset and bit size.
* printcmd.c (print_scalar_formatted): Handle zero-length
integer.
(print_scalar_formatted): Use bit_size_differs_p.
* gdbtypes.h (enum type_specific_kind) <TYPE_SPECIFIC_INT>: New
constant.
(union type_specific): <int_stuff>: New member.
(struct type) <bit_size_differs_p, bit_size, bit_offset>: New
methods.
* gdbtypes.c (init_integer_type, init_boolean_type): Initialize
TYPE_SPECIFIC_FIELD.
(recursive_dump_type, copy_type_recursive): Update.
* dwarf2/read.c (read_base_type): Handle DW_AT_bit_size and
DW_AT_data_bit_offset.
gdb/testsuite/ChangeLog
2020-09-23 Tom Tromey <tom@tromey.com>
* gdb.dwarf2/intbits.exp: New file.
* gdb.dwarf2/intbits.c: New file.
This changes some functions in dwarf2/read.c to avoid
bfd_map_over_sections, in favor of iteration.
gdb/ChangeLog
2020-09-19 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (locate_dwz_sections): Change parameters.
(dwarf2_get_dwz_file): Use foreach.
(dwarf2_locate_dwo_sections): Change parameters.
(open_and_init_dwo_file): Use foreach.
(dwarf2_locate_common_dwp_sections): Change parameters.
(open_and_init_dwp_file): Use foreach.
This changes dwarf2/read.c to use htab_up rather than explicit calls
to htab_delete.
gdb/ChangeLog
2020-09-17 Tom Tromey <tom@tromey.com>
* dwarf2/read.c (compute_compunit_symtab_includes): Use htab_up.
When store_sym_names_in_linkage_form_p was introduced in this commit:
commit 59cc4834e5
Date: Tue Mar 27 08:57:16 2018 -0500
problem looking up some symbols when they have a linkage name
A special case was left behind for Go, however, this special case was
not really needed anymore, it could be handled by having
store_sym_names_in_linkage_form_p return the true for go, instead of
false.
This commit overrides store_sym_names_in_linkage_form_p for Go, and
then removes the special case. As store_sym_names_in_linkage_form_p
is only called once throughout GDB this should be perfectly safe.
There should be no user visible changes after this commit.
gdb/ChangeLog:
* dwarf2/read.c (dwarf2_physname): Remove special case for
language_go.
* go-lang.c (go_language::store_sym_names_in_linkage_form_p): New
member function.
A later patch in this series will rewrite enum_flags fixing some API
holes. That would cause build failures around code using
type_instance_flags. Or rather, that should be using it, but wasn't.
This patch fixes it by using type_instance_flags throughout instead of
plain integers.
Note that we can't make the seemingly obvious change to struct
type::instance_flags:
- unsigned instance_flags : 9;
+ ENUM_BITFIELD (type_instance_flag_value) instance_flags : 9;
Because G++ complains then that 9 bits isn't sufficient for holding
all values of type_instance_flag_value.
So the patch adds an type::instance_flags() method, which takes care
of casting appropriately, and adds a separate type::set_instance_flags
method, following the pattern of the ongoing TYPE_XXX macro
elimination. This converts uses of TYPE_INSTANCE_FLAGS to
type::instance_flags() in the places where the code was already being
touched, but there are still many references to the
TYPE_INSTANCE_FLAGS macro left behind. Those could/should be fully
replaced at some point.
gdb/ChangeLog:
* avr-tdep.c (avr_address_class_type_flags): Return
type_instance_flags.
(avr_address_class_type_flags_to_name): Take a
type_instance_flags.
(avr_address_class_name_to_type_flags): Return bool and take a
type_instance_flags.
* d-lang.c (build_d_types): Use type::set_instance_flags.
* ft32-tdep.c (ft32_address_class_type_flags): Return
type_instance_flags.
(ft32_address_class_type_flags_to_name): Take a
type_instance_flags.
(ft32_address_class_name_to_type_flags): Return bool and take a
type_instance_flags.
(ft32_gdbarch_init): Use type::set_instance_flags.
* eval.c (fake_method::fake_method): Use type::set_instance_flags.
* gdbarch.h, gdbarch.c: Regenerate.
* gdbarch.sh (address_class_type_flags): Use type_instance_flags.
(address_class_name_to_type_flags): Use type_instance_flags and
bool.
* gdbtypes.c (address_space_name_to_int)
(address_space_int_to_name, make_qualified_type): Use
type_instance_flags.
(make_qualified_type): Use type_instance_flags and
type::set_instance_flags.
(make_type_with_address_space, make_cv_type, make_vector_type)
(check_typedef): Use type_instance_flags.
(recursive_dump_type): Cast type_instance_flags to unsigned for
printing.
(copy_type_recursive): Use type::set_instance_flags.
(gdbtypes_post_init): Use type::set_instance_flags.
* gdbtypes.h (struct type) <instance_flags>: Rename to ...
<m_instance_flags>: ... this.
<instance_flags, set_instance_flags>: New methods.
(TYPE_INSTANCE_FLAGS): Use the instance_flags method.
(SET_TYPE_INSTANCE_FLAGS): New.
(address_space_name_to_int, address_space_int_to_name)
(make_type_with_address_space): Pass flags using
type_instance_flags instead of int.
* stabsread.c (cleanup_undefined_types_noname): Use
type::set_instance_flags.
* s390-tdep.c (s390_address_class_type_flags): Return
type_instance_flags.
(s390_address_class_type_flags_to_name): Take a
type_instance_flags.
(s390_address_class_name_to_type_flags): Return bool and take a
type_instance_flags.
* type-stack.c (type_stack::follow_types): Use
type_instance_flags.
* dwarf2/read.c (read_tag_pointer_type): Use type_instance_flags.
Add the `endianity_is_not_default` and `set_endianity_is_not_default`
methods on `struct type`, in order to remove the
`TYPE_ENDIANITY_NOT_DEFAULT` macro. In this patch, the macro is changed
to use the getter, so all the call sites of the macro that are used as a
setter are changed to use the setter method directly. The next patch
will remove the macro completely.
gdb/ChangeLog:
* gdbtypes.h (struct type) <endianity_is_not_default,
set_endianity_is_not_default>: New methods.
(TYPE_ENDIANITY_NOT_DEFAULT): Use
type::endianity_is_not_default, change all write call sites to
use type::set_endianity_is_not_default.
Change-Id: I67acd68fcdae424d7e4a601afda78612ad5d92db
Add the `stub_is_supported` and `set_stub_is_supported` methods on `struct type`, in
order to remove the `TYPE_STUB_SUPPORTED` macro. In this patch, the macro is
changed to use the getter, so all the call sites of the macro that are
used as a setter are changed to use the setter method directly. The
next patch will remove the macro completely.
gdb/ChangeLog:
* gdbtypes.h (struct type) <stub_is_supported, set_stub_is_supported>: New methods.
(TYPE_STUB_SUPPORTED): Use type::stub_is_supported, change all write call sites to
use type::set_stub_is_supported.
Change-Id: I4dfecf2b5df9c2b7bb8db1e9252082140adf3028
Add the `has_varargs` and `set_has_varargs` methods on `struct type`, in
order to remove the `TYPE_VARARGS` macro. In this patch, the macro is
changed to use the getter, so all the call sites of the macro that are
used as a setter are changed to use the setter method directly. The
next patch will remove the macro completely.
gdb/ChangeLog:
* gdbtypes.h (struct type) <has_varargs, set_has_varargs>: New methods.
(TYPE_VARARGS): Use type::has_varargs, change all write call sites to
use type::set_has_varargs.
Change-Id: I898a1093ae40808b37a7c6fced7f6fa2aae604de
Add the `is_prototyped` and `set_is_prototyped` methods on `struct
type`, in order to remove the `TYPE_PROTOTYPED` macro. In this patch,
the macro is changed to use the getter, so all the call sites of the
macro that are used as a setter are changed to use the setter method
directly. The next patch will remove the macro completely.
gdb/ChangeLog:
* gdbtypes.h (struct type) <is_prototyped, set_is_prototyped>:
New methods.
(TYPE_PROTOTYPED): Use type::is_prototyped, change all write
call sites to use type::set_is_prototyped.
Change-Id: I6ba285250fae413f7c1bf2ffcb5a2cedc8e743da
Add the `target_is_stub` and `set_target_is_stub` methods on `struct
type`, in order to remove the `TYPE_TARGET_STUB` macro. In this patch,
the macro is changed to use the getter, so all the call sites of the
macro that are used as a setter are changed to use the setter method
directly. The next patch will remove the macro completely.
gdb/ChangeLog:
* gdbtypes.h (struct type) <target_is_stub, set_target_is_stub>:
New methods.
(TYPE_TARGET_STUB): Use type::is_stub, change all write call
sites to use type::set_target_is_stub.
Change-Id: I9c71a89adc7ae8d018db9ee156f41c623be0484a
Add the `is_stub` and `set_is_stub` methods on `struct type`, in order
to remove the `TYPE_STUB` macro. In this patch, the macro is changed to
use the getter, so all the call sites of the macro that are used as a
setter are changed to use the setter method directly. The next patch
will remove the macro completely.
gdb/ChangeLog:
* gdbtypes.h (struct type) <is_stub, set_is_stub>: New methods.
(TYPE_STUB): Use type::is_stub, change all write call sites to
use type::set_is_stub.
Change-Id: Ie935e8fe72c908afd8718411e83f4ff00c386bf3
Add the `has_no_signedness` and `set_has_no_signednes` methods on `struct
type`, in order to remove the `TYPE_NOSIGN` macro. In this patch, the macro is
changed to use the getter, so all the call sites of the macro that are used as
a setter are changed to use the setter method directly. The next patch will
remove the macro completely.
gdb/ChangeLog:
* gdbtypes.h (struct type) <has_no_signedness,
set_has_no_signedness>: New methods.
(TYPE_NOSIGN): Use type::has_no_signedness, change all write
call sites to use type::set_has_no_signedness.
Change-Id: I80d8e774316d146fbd814b2928ad5392bada39d5
Add the `is_unsigned` and `set_is_unsigned` methods on `struct type`, in
order to remove the `TYPE_UNSIGNED` macro. In this patch, the
`TYPE_UNSIGNED` macro is changed to use `type::is_unsigned`, so all the
call sites that are used to set this property on a type are changed to
use the new method. The next patch will remove the macro completely.
gdb/ChangeLog:
* gdbtypes.h (struct type) <is_unsigned, set_is_unsigned>: New
methods.
(TYPE_UNSIGNED): Use type::is_unsigned. Change all write call
sites to use type::set_is_unsigned.
Change-Id: Ib09ddce84eda160a801a8f288cccf61c8ef136bc
When adding:
...
if ![runto_main] then {
fail "can't run to main"
return 0
}
...
to test-case gdb.base/label-without-address.exp and running it with target
board unix/-fPIE/-pie, we run into:
...
(gdb) break main:L1^M
Breakpoint 2 at 0x555555554000: file label-without-address.c, line 22.^M
...
That is, for a label with optimized-out address, we set a breakpoint at the
relocation base.
The root cause is that the dwarf reader, despite finding that attribute
DW_AT_low_pc is missing, still tags the L1 symbol as having LOC_LABEL, which
means it has a valid address, which defaults to 0.
Fix this by instead tagging the L1 symbol with LOC_OPTIMIZED_OUT.
Tested on x86_64-linux.
gdb/ChangeLog:
2020-09-03 Tom de Vries <tdevries@suse.de>
PR breakpoint/26546
* dwarf2/read.c (new_symbol): Tag label symbol without DW_AT_low_pc as
LOC_OPTIMIZED_OUT instead of LOC_LABEL.
gdb/testsuite/ChangeLog:
2020-09-03 Tom de Vries <tdevries@suse.de>
PR breakpoint/26546
* gdb.base/label-without-address.exp: Runto main first.
gdb/ChangeLog:
* dwarf2/read.c (struct field_info) <non_public_fields>: Change
type to bool.
(dwarf2_add_field): Use true instead of 1.
Change-Id: I7e9c86429402c28d4f15861d17976b9c50049f94
The indentation is off, fix it before doing other changes.
gdb/ChangeLog:
* dwarf2/read.c (struct field_info): Fix indentation.
Change-Id: Ife6a3d017abcf0a33e49e47e51429e95d504343c
Replace the function pointer + `void *` parameters of
dwarf2_fetch_die_loc_sect_off and dwarf2_fetch_die_loc_cu_off with a
function_view parameter. Change call sites to use a lambda function.
This improves type-safety, so reduces the chances of errors.
gdb/ChangeLog:
* read.h (dwarf2_fetch_die_loc_sect_off,
dwarf2_fetch_die_loc_cu_off): Replace function pointer +
`void *` parameter with function_view.
* read.c (dwarf2_fetch_die_loc_sect_off,
dwarf2_fetch_die_loc_cu_off): Likewise.
* loc.c (get_frame_pc_for_per_cu_dwarf_call): Remove.
(per_cu_dwarf_call): Adjust.
(get_frame_address_in_block_wrapper): Remove.
(indirect_synthetic_pointer): Adjust.
(get_ax_pc): Remove.
(dwarf2_compile_expr_to_ax): Adjust.
Change-Id: Ic9b6ced0c4128f2b75ca62e0ed638b0962a22859
The DWARF v5 Spec describes a (slightly) new format for V5 .dwp files.
This patch updates GDB to allow it to read/process .dwp files in the
new DWARF v5 format, while continuing to be able to read/process .dwp files
in the older V1 & V2 formats (older, pre-standard formats).
The two major differences between the V2 and the V5 format are:
- The inclusion of DWARF-v5-specific sections:
.debug_loclists.dwo
.debug_rnglists.dwo
- The .dwp section identifier encodings have changed. The table below
shows the old & new encodings. Notice the re-purposing of 5, 7 & 8
in particular.
Val DW4 section DW4 section id DW5 section DW5 section id
--- ----------------- -------------- ----------------- --------------
1 .debug_info.dwo DW_SECT_INFO .debug_info.dwo DW_SECT_INFO
2 .debug_types.dwo DW_SECT_TYPES -- reserved
3 .debug_abbrev.dwo DW_SECT_ABBREV .debug_abbrev.dwo DW_SECT_ABBREV
4 .debug_line.dwo DW_SECT_LINE .debug_line.dwo DW_SECT_LINE
5 .debug_loc.dwo DW_SECT_LOC .debug_loclists.dwo DW_SECT_LOCLISTS
6 .debug_str_offsets.dwo .debug_str_offsets.dwo
DW_SECT_STR_OFFSETS DW_SECT_STR_OFFSETS
7 .debug_macinfo.dwo DW_SECT_MACINFO .debug_macro.dwo DW_SECT_MACRO
8 .debug_macro.dwo DW_SECT_MACRO .debug_rnglists.dwo DW_SECT_RNGLISTS
Older Rust compilers used special field names, rather than DWARF
features, to express the variant parts of Rust enums. This is handled
in gdb through a quirk recognizer that rewrites the types.
Tom de Vries pointed out in PR rust/26197 that the variant part
rewrite regressed this code. This patch fixes the problems:
* Univariant enums were not handled properly. Now we simply call
alloc_rust_variant for these as well.
* There was an off-by-one error in the handling of ordinary enums.
* Ordinary enums should have the size of their member types reset to
match the size of the enclosing enum. (It's not clear to me if this
is truly necessary, but it placates a test, and this is just legacy
handling in any case.)
Tested with Rust 1.12.0, 1.14.0, 1.19.0, 1.36.0, and 1.45.0 on x86-64
Fedora 32. There were some unrelated failures with 1.14.0 and 1.19,0;
but considering that these are fairly old releases, I don't plan to
look into them unless someone complains.
Note that this patch will not fix all the issues in the PR. In that
PR, Tom is using a somewhat unusual build of Rust -- in particular it
uses an older (pre-DWARF variant part) LLVM with a newer Rust. I
believe this compiler doesn't correctly implement the old-style name
fallback; the details are in the bug.
gdb/ChangeLog
2020-08-05 Tom Tromey <tromey@adacore.com>
PR rust/26197:
* dwarf2/read.c (alloc_rust_variant): Handle univariant case.
(quirk_rust_enum): Call alloc_rust_variant for univariant case.
Fix off-by-one and type size errors in ordinary case.
When reverting commit 9cfd2b89bd "[gdb/testsuite] Fix
gdb.arch/amd64-entry-value-paramref.S", we run into an internal-error:
...
(gdb) file amd64-entry-value-paramref^M
Reading symbols from amd64-entry-value-paramref...^M
src/gdb/dwarf2/read.c:18903: internal-error: could not find partial DIE
0x1b7 in cache [from module amd64-entry-value-paramref]^M
A problem internal to GDB has been detected,^M
further debugging may prove unreliable.^M
...
because of invalid dwarf.
In contrast, when using -readnow, we have:
...
(gdb) file -readnow amd64-entry-value-paramref
Reading symbols from amd64-entry-value-paramref...
Expanding full symbols from amd64-entry-value-paramref...
Dwarf Error: Cannot find DIE at 0x1b7 referenced from DIE at 0x11a \
[in module amd64-entry-value-paramref]
(gdb)
...
Change the internal error into a Dwarf Error, such that we have:
...
(gdb) file amd64-entry-value-paramref^M
Reading symbols from amd64-entry-value-paramref...^M
Dwarf Error: Cannot not find DIE at 0x1b7 \
[from module amd64-entry-value-paramref]^M
^M
(No debugging symbols found in amd64-entry-value-paramref)^M
(gdb)
...
Build and tested on x86_64-linux.
gdb/ChangeLog:
2020-08-04 Tom de Vries <tdevries@suse.de>
PR symtab/23270
* dwarf2/read.c (find_partial_die): Change internal error into Dwarf
Error.
When reading an exec with a .debug_line section containing a vendor-specific
extended opcode, we get:
...
$ gdb -batch -iex "set complaints 10" dw2-vendor-extended-opcode
During symbol reading: mangled .debug_line section
...
and reading of the .debug_line section is abandoned.
The vendor-specific extended opcode should be ignored, as specified in the
DWARF standard (7.1 Vendor Extensibility). [ FWIW, vendor-specific
standard opcodes are already ignored. ]
Fix this by ignoring all vendor-specific extended opcodes.
Build and tested on x86_64-linux.
gdb/ChangeLog:
2020-08-03 Tom de Vries <tdevries@suse.de>
PR symtab/26333
* dwarf2/read.c (dwarf_decode_lines_1): Ignore
DW_LNE_lo_user/DW_LNE_hi_user range.
gdb/testsuite/ChangeLog:
2020-08-03 Tom de Vries <tdevries@suse.de>
PR symtab/26333
* lib/dwarf.exp (DW_LNE_user): New proc.
* gdb.dwarf2/dw2-vendor-extended-opcode.c: New test.
* gdb.dwarf2/dw2-vendor-extended-opcode.exp: New file.
The DWARF standard states for the line register in the line number information
state machine the following:
...
An unsigned integer indicating a source line number. Lines are numbered
beginning at 1. The compiler may emit the value 0 in cases where an
instruction cannot be attributed to any source line.
...
So, it's possible to have a zero line number in the DWARF line table.
This is currently not handled by GDB. The zero value is read in as any other
line number, but internally the zero value has a special meaning:
end-of-sequence, so the line table entry ends up having a different
interpretation than intended in some situations.
I've created a test-case where various aspects are tested, which has these 4
interesting tests.
1. Next-step through a zero-line instruction, is_stmt == 1
gdb.dwarf2/dw2-line-number-zero.exp: bar1, 2nd next
2. Next-step through a zero-line instruction, is_stmt == 0
gdb.dwarf2/dw2-line-number-zero.exp: bar2, 2nd next
3. Show source location at zero-line instruction, is_stmt == 1
gdb.dwarf2/dw2-line-number-zero.exp: continue to breakpoint: bar1_label_3
4. Show source location at zero-line instruction, is_stmt == 0
gdb.dwarf2/dw2-line-number-zero.exp: continue to breakpoint: bar2_label_3
And we have the following results:
8.3.1, 9.2:
...
FAIL: gdb.dwarf2/dw2-line-number-zero.exp: bar1, 2nd next
PASS: gdb.dwarf2/dw2-line-number-zero.exp: bar2, 2nd next
PASS: gdb.dwarf2/dw2-line-number-zero.exp: continue to breakpoint: bar1_label_3
FAIL: gdb.dwarf2/dw2-line-number-zero.exp: continue to breakpoint: bar2_label_3
...
commit 8c95582da8 "gdb: Add support for tracking the DWARF line table is-stmt
field":
...
PASS: gdb.dwarf2/dw2-line-number-zero.exp: bar1, 2nd next
PASS: gdb.dwarf2/dw2-line-number-zero.exp: bar2, 2nd next
FAIL: gdb.dwarf2/dw2-line-number-zero.exp: continue to breakpoint: bar1_label_3
FAIL: gdb.dwarf2/dw2-line-number-zero.exp: continue to breakpoint: bar2_label_3
...
commit d8cc8af6a1 "[gdb/symtab] Fix line-table end-of-sequence sorting",
master:
FAIL: gdb.dwarf2/dw2-line-number-zero.exp: bar1, 2nd next
FAIL: gdb.dwarf2/dw2-line-number-zero.exp: bar2, 2nd next
PASS: gdb.dwarf2/dw2-line-number-zero.exp: continue to breakpoint: bar1_label_3
PASS: gdb.dwarf2/dw2-line-number-zero.exp: continue to breakpoint: bar2_label_3
...
The regression in test 2 at commit d8cc8af6a1 was filed as PR symtab/26243,
where clang emits zero line numbers.
The way to fix all tests is to make sure line number zero internally doesn't
clash with special meaning values, and by handling it appropriately
everywhere. That however looks too intrusive for the GDB 10 release.
Instead, we decide to ensure defined behaviour for line number zero by
ignoring it. This gives us back the test results from before commit
d8cc8af6a1, fixing PR26243.
We mark the FAILs for tests 3 and 4 as KFAILs. Test 4 was already failing for
the 9.2 release, and we consider the regression of test 3 from gdb 9.2 to gdb
10 the cost for having defined behaviour.
Build and reg-tested on x86_64-linux.
gdb/ChangeLog:
2020-07-25 Tom de Vries <tdevries@suse.de>
PR symtab/26243
* dwarf2/read.c (lnp_state_machine::record_line): Ignore zero line
entries.
gdb/testsuite/ChangeLog:
2020-07-25 Tom de Vries <tdevries@suse.de>
PR symtab/26243
* gdb.dwarf2/dw2-line-number-zero.c: New test.
* gdb.dwarf2/dw2-line-number-zero.exp: New file.
While experimenting with GDB on DWARF 5 with split debug (dwo files),
I discovered that GDB was not reading the rnglist index
properly (it needed to be reprocessed in the same way the loclist
index does), and that there was no code for reading rnglists out of
dwo files at all. Also, the rnglist address reading function
(dwarf2_rnglists_process) was adding the base address to all rnglist
entries, when it's only supposed to add it to the DW_RLE_offset_pair
entries (http://dwarfstd.org/doc/DWARF5.pdf, p. 53), and was not
handling several entry types.
- Added 'reprocessing' for reading rnglist index (as is done for loclist
index).
- Added code for reading rnglists out of .dwo files.
- Added several missing rnglist forms to dwarf2_rnglists_process.
- Fixed bug that was alwayas adding base address for rnglists (only
one form needs that).
- Updated dwarf2_rnglists_process to read rnglist out of dwo file when
appropriate.
- Added new functions cu_debug_rnglist_section & read_rnglist_index.
- Added new testcase, dw5-rnglist-test.{cc,exp}
Special note about the new testcase:
In order for the test case to test anything meaningful, it must be
compiled with clang, not GCC. The way to do this is as follows:
$ make check RUNTESTFLAGS="CC_FOR_TARGET=/path/to/clang CXX_FOR_TARGET=/path/to/clang++ dw5-rnglist-test.exp"
This following version of clang was used for this testing:
clang version 9.0.1-11
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
Change-Id: I3053c5ddc345720b8ed81e23a88fe537ab38748d
Add setters, to ensure that the kind and value of the property are
always kept in sync (a caller can't forget one or the other). Add
getters, such that we can assert that when a caller accesses a data bit
of the property, the property is indeed of the corresponding kind.
Note that because of the way `struct dynamic_prop` is allocated
currently, we can't make the `m_kind` and `m_data` fields private. That
would make the type non-default-constructible, and we would have to call
the constructor when allocating them. However, I still prefixed them
with `m_` to indicate that they should not be accessed from outside the
class (and also to be able to use the name `kind` for the method).
gdb/ChangeLog:
* gdbtypes.h (struct dynamic_prop) <kind, set_undefined,
const_val, set_const_val, baton, set_locexpr, set_loclist,
set_addr_offset, variant_parts, set_variant_parts,
original_type, set_original_type>: New methods.
<kind>: Rename to...
<m_kind>: ... this. Update all users to use the new methods
instead.
<data>: Rename to...
<m_data>: ... this. Update all users to use the new methods
instead.
Change-Id: Ib72a8eb440dfeb1a5421d0933334230d7f2478f9
Remove it in favor of using type::bounds directly.
gdb/ChangeLog:
* gdbtypes.h (TYPE_RANGE_DATA): Remove. Update callers to use
the type::bounds method directly.
Change-Id: Id4fab22af0a94cbf505f78b01b3ee5b3d682fba2
LLD from 11 onwards (https://reviews.llvm.org/D81784) uses -1 to
represent a relocation in .debug_line referencing a discarded symbol.
Recognize -1 to fix gdb.base/break-on-linker-gcd-function.exp when the
linker is a newer LLD.
gdb/ChangeLog:
* dwarf2/read.c (lnp_state_machine::check_line_address): Test -1.
Currently, GDB rejects the (die) reference form while it accepts exprloc
form. It is allowed in DWARF standard. "Table 7.5: Attribute encodings"
in DWARF5 standard. Flang compiler assigns (die) reference to
DW_AT_associated and DW_AT_allocated for some cases.
gdb/ChangeLog
* dwarf2/read.c (set_die_type): Removed conditions to restrict
forms for DW_AT_associated and DW_AT_allocated attributes,
which is already checked in function attr_to_dynamic_prop.
Tom de Vries pointed out that some Rust tests were failing after the
variant part rewrite. He sent an executable, which helped track down
this bug.
quirk_rust_enum was passing 1 to alloc_rust_variant in one case.
However, a comment earlier says:
/* We don't need a range entry for the discriminant, but we do
need one for every other field, as there is no default
variant. */
In this case, we must pass -1 for this parameter. That is what this
patch implements.
gdb/ChangeLog
2020-06-30 Tom Tromey <tromey@adacore.com>
* dwarf2/read.c (quirk_rust_enum): Correctly call
alloc_rust_variant for default-less enum.
This patch fixes an internal error that is triggered when loading the
same binary twice with the index-cache on:
$ ./gdb -q -nx --data-directory=data-directory
(gdb) set index-cache on
(gdb) shell mktemp -d
/tmp/tmp.BLgouVoPq4
(gdb) set index-cache directory /tmp/tmp.BLgouVoPq4
(gdb) file a.out
Reading symbols from a.out...
(gdb) file a.out
Load new symbol table from "a.out"? (y or n) y
Reading symbols from a.out...
/home/smarchi/src/binutils-gdb/gdb/dwarf2/read.c:2540: internal-error: void create_cus_from_index(dwarf2_per_bfd*, const gdb_byte*, offset_type, const gdb_byte*, offset_type): Assertion `per_bfd->all_comp_units.empty ()' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n)
This is what happens:
1. We load the binary the first time, partial symtabs are created,
per_bfd->all_comp_units is filled from those.
2. Because index-cache is on, we also generate an index in the cache.
3. We load the binary a second time, in dwarf2_initialize_objfile we
check: was an index already loaded for this BFD? No, so we try to
read the index and fill the per-bfd using it. We do find an index,
it's in the cache.
4. The function create_cus_from_index asserts (rightfully) that
per_cu->all_comp_units is empty, and the assertion fails.
This assertion verifies that we are not reading an index for a BFD for
which we have already built partial symtabs or read another index.
The index-cache gives a situation that isn't currently accounted for: a
BFD for which we have built the partial symtabs the first time, but has
an index the second time.
This patch addresses it by checking for the presence of partial symtabs
in dwarf2_initialize_objfile. If there are, we don't try reading the
index.
gdb/ChangeLog:
* dwarf2/read.c (dwarf2_initialize_objfile): Check for presence
of partial symtabs.
gdb/testsuite/ChangeLog:
* gdb.base/index-cache-load-twice.c: New.
* gdb.base/index-cache-load-twice.exp: New.
Change-Id: Ie05474c44823fcdff852b73170dd28dfd66cb6a2
This commit changes the language_data::la_get_symbol_name_matcher
function pointer member variable into a member function of
language_defn.
There should be no user visible changes after this commit.
Before this commit access to the la_get_symbol_name_matcher function
pointer was through the get_symbol_name_matcher function, which looked
something like this (is pseudo-code):
<return-type>
get_symbol_name_matcher (language_defn *lang, <other args>)
{
if (current_language == ada)
current_language->la_get_symbol_name_matcher (<other args>);
else
lang->la_get_symbol_name_matcher (<other args>);
}
In this commit I moved the get_symbol_name_matcher as a non-virtual
function in the language_defn base class, I then add a new virtual
method that is only used from within get_symbol_name_matcher, this can
then be overridden by specific languages as needed. So we now have:
class language_defn
{
<return-type> get_symbol_name_matcher (<args>)
{
if (current_language == ada)
return current_language->get_symbol_name_matcher_inner (<args>);
else
return this->get_symbol_name_matcher_inner (<args>);
}
virtual <return-type> get_symbol_name_matcher_inner (<args>)
{
....
}
}
gdb/ChangeLog:
* ada-lang.c (ada_get_symbol_name_matcher): Update header comment.
(ada_language_data): Delete la_get_symbol_name_matcher
initializer.
(language_defn::get_symbol_name_matcher_inner): New member
function.
* c-lang.c (c_language_data): Delete la_get_symbol_name_matcher
initializer.
(cplus_language_data): Likewise.
(cplus_language::get_symbol_name_matcher_inner): New member
function.
(asm_language_data): Delete la_get_symbol_name_matcher initializer.
(minimal_language_data): Likewise.
* cp-support.h (cp_get_symbol_name_matcher): Update header comment.
* d-lang.c (d_language_data): Delete la_get_symbol_name_matcher
initializer.
* dictionary.c (iter_match_first_hashed): Update call to
get_symbol_name_matcher.
(iter_match_next_hashed): Likewise.
(iter_match_next_linear): Likewise.
* dwarf2/read.c (dw2_expand_symtabs_matching_symbol): Likewise.
* f-lang.c (f_language_data): Delete la_get_symbol_name_matcher
initializer.
(f_language::get_symbol_name_matcher_inner): New member function.
* go-lang.c (go_language_data): Delete la_get_symbol_name_matcher
initializer.
* language.c (default_symbol_name_matcher): Update header comment,
make static.
(language_defn::get_symbol_name_matcher): New definition.
(language_defn::get_symbol_name_matcher_inner): Likewise.
(get_symbol_name_matcher): Delete.
(unknown_language_data): Delete la_get_symbol_name_matcher
initializer.
(auto_language_data): Likewise.
* language.h (language_data): Delete la_get_symbol_name_matcher
field.
(language_defn::get_symbol_name_matcher): New member function.
(language_defn::get_symbol_name_matcher_inner): Likewise.
(default_symbol_name_matcher): Delete declaration.
* linespec.c (find_methods): Update call to
get_symbol_name_matcher.
* m2-lang.c (m2_language_data): Delete la_get_symbol_name_matcher
initializer.
* minsyms.c (lookup_minimal_symbol): Update call to
get_symbol_name_matcher.
(iterate_over_minimal_symbols): Likewise.
* objc-lang.c (objc_language_data): Delete
la_get_symbol_name_matcher initializer.
* opencl-lang.c (opencl_language_data): Likewise.
* p-lang.c (pascal_language_data): Likewise.
* psymtab.c (psymbol_name_matches): Update call to
get_symbol_name_matcher.
* rust-lang.c (rust_language_data): Delete
la_get_symbol_name_matcher initializer.
* symtab.c (symbol_matches_search_name): Update call to
get_symbol_name_matcher.
(compare_symbol_name): Likewise.
Currently the .gdb_index is not enabled for ada executables (PR24713).
Fix this by adding the required support in write_psymbols, similar to how that
is done for .debug_names in debug_names::insert.
Tested on x86_64-linux, with native and target board cc-with-gdb-index.
gdb/ChangeLog:
2020-06-10 Tom de Vries <tdevries@suse.de>
PR ada/24713
* dwarf2/index-write.c (struct mapped_symtab): Add m_string_obstack.
(write_psymbols): Enable .gdb_index for ada.
* dwarf2/read.c: Remove comment stating .gdb_index is unsupported for
ada.
gdb/testsuite/ChangeLog:
2020-06-10 Tom de Vries <tdevries@suse.de>
* gdb.ada/ptype_union.exp: Remove PR24713 workaround.
In commit 9a0bacfb08 "[gdb/symtab] Handle .gdb_index in ada language mode", a
missing part of dw2_map_matching_symbols was added, containing a call to
dw2_expand_symtabs_matching_symbol.
However, the callback passed to that call has one problem: the callback has an
argument "offset_type namei", which is ignored. Instead, match_name is passed
as argument to dw2_symtab_iter_init, where a name lookup is done, which may or
may not yield the same value as namei.
Fix this by creating a new version of dw2_symtab_iter_init that takes a
"offset_type namei" argument instead of "const char *name", and passing namei.
Tested on x86_64-linux, with native and target board cc-with-gdb-index.
gdb/ChangeLog:
2020-06-10 Tom de Vries <tdevries@suse.de>
* dwarf2/read.c (dw2_symtab_iter_init_common): Factor out of ...
(dw2_symtab_iter_init): ... here. Add variant with "offset_type
namei" instead of "const char *name" argument.
(dw2_map_matching_symbols): Use "offset_type namei" variant of
dw2_symtab_iter_init.
Remove the `TYPE_FIELD_TYPE` macro, changing all the call sites to use
`type::field` and `field::type` directly.
gdb/ChangeLog:
* gdbtypes.h (TYPE_FIELD_TYPE): Remove. Change all call sites
to use type::field and field::type instead.
Change-Id: Ifda6226a25c811cfd334a756a9fbc5c0afdddff3
Remove the `FIELD_TYPE` macro, changing all the call sites to use
`field::type` directly.
gdb/ChangeLog:
* gdbtypes.h (FIELD_TYPE): Remove. Change all call sites
to use field::type instead.
Change-Id: I7673fedaa276e485189c87991a9043495da22ef5
Add the `type` and `set_type` methods on `struct field`, in order to
remoremove the `FIELD_TYPE` macro. In this patch, the `FIELD_TYPE`
macro is changed to use `field::type`, so all the call sites that are
useused to set the field's type are changed to use `field::set_type`.
The next patch will remove `FIELD_TYPE` completely.
Note that because of the name clash between the existing field named
`type` and the new method, I renamed the field `m_type`. It is not
private per-se, because we can't make `struct field` a non-POD yet, but
it should be considered private anyway (not accessed outside `struct
field`).
gdb/ChangeLog:
* gdbtypes.h (struct field) <type, set_type>: New methods.
Rename `type` field to...
<m_type>: ... this. Change references throughout to use type or
set_type methods.
(FIELD_TYPE): Use field::type. Change call sites that modify
the field's type to use field::set_type instead.
Change-Id: Ie21f866e3b7f8a51ea49b722d07d272a724459a0
Fix/follow-up to commit 17ee85fc2a ("Share DWARF partial symtabs").
In the non-index case, where GDB builds partial symbols from scratch,
two objfiles around the same BFD correctly share partial symtabs. The
first objfile, which has to do all the work, saves a reference to the
created partial symtabs in the shared per_bfd object (at the end of
dwarf2_build_psymtabs). The second objfile, when it reaches
dwarf2_build_psymtabs, sees that there are already partial symtabs built
for this BFD and just uses it.
However, that commit missed implementing the same sharing for cases
where GDB uses .gdb_index or .debug_names to build the partial symtabs.
This patch fixes it by having the first objfile to use the BFD set
per_bfd->partial_symtabs at the end of dwarf2_read_gdb_index /
dwarf2_read_debug_names. For the subsequent objfiles using that BFD,
the partial symtabs are then picked up in dwarf2_initialize_objfile.
This patch adds a test that mimics how the issue was originally
triggered:
1. Load the test file twice, such that the second objfile re-uses the
per_bfd object created for the first objfile.
2. Run to some point where in the backtrace there is a frame for a
function that's in a CU that's not yet read in.
3. Check that this frame's information is complete in the "backtrace"
output.
Step 2 requires an address -> symbol lookup which uses the addrmap at
objfile->partial_symtabs->psymtabs_addrmap. If the
objfile->partial_symtabs link is not properly setup (as is the case
before this patch), the symbol for that frame won't be found and we'll
get a frame with incomplete information.
The test fails without the fix when using boards "cc-with-gdb-index" and
"cc-with-debug-names".
gdb/ChangeLog:
* dwarf2/read.c (dwarf2_read_gdb_index): Save partial_symtabs in
the per_bfd object.
(dwarf2_read_debug_names): Likewise.
(dwarf2_initialize_objfile): Use partial_symtabs from per_bfd
object when re-using a per_bfd object with an index.
gdb/testsuite/ChangeLog:
* gdb.dwarf2/share-psymtabs-bt.exp: New file.
* gdb.dwarf2/share-psymtabs-bt.c: New file.
* gdb.dwarf2/share-psymtabs-bt-2.c: New file.
Change-Id: Ibb26210e2dfc03b80ba9fa56b875ba4cc58c0352
Consider the test-case contained in this patch.
With -readnow, we have two breakpoint locations:
...
$ gdb -readnow -batch breakpoint-locs -ex "b N1::C1::baz" -ex "info break"
Breakpoint 1 at 0x4004cb: N1::C1::baz. (2 locations)
Num Type Disp Enb Address What
1 breakpoint keep y <MULTIPLE>
1.1 y 0x00000000004004cb in N1::C1::baz() \
at breakpoint-locs.h:6
1.2 y 0x00000000004004f0 in N1::C1::baz() \
at breakpoint-locs.h:6
...
But without -readnow, we have instead only one breakpoint location:
...
$ gdb -batch breakpoint-locs -ex "b N1::C1::baz" -ex "info break"
Breakpoint 1 at 0x4004f0: file breakpoint-locs.h, line 6.
Num Type Disp Enb Address What
1 breakpoint keep y 0x00000000004004f0 in N1::C1::baz() \
at breakpoint-locs.h:6
...
The relevant dwarf is this bit:
...
<0><d2>: Abbrev Number: 1 (DW_TAG_compile_unit)
<d8> DW_AT_name : breakpoint-locs.cc
<1><f4>: Abbrev Number: 2 (DW_TAG_namespace)
<f5> DW_AT_name : N1
<2><fe>: Abbrev Number: 3 (DW_TAG_class_type)
<ff> DW_AT_name : C1
<3><109>: Abbrev Number: 4 (DW_TAG_subprogram)
<10a> DW_AT_name : baz
<110> DW_AT_linkage_name: _ZN2N12C13bazEv
<2><116>: Abbrev Number: 5 (DW_TAG_subprogram)
<117> DW_AT_name : foo
<11d> DW_AT_linkage_name: _ZN2N13fooEv
<1><146>: Abbrev Number: 8 (DW_TAG_subprogram)
<147> DW_AT_specification: <0x116>
<14b> DW_AT_low_pc : 0x4004c7
<153> DW_AT_high_pc : 0x10
<2><161>: Abbrev Number: 9 (DW_TAG_inlined_subroutine)
<162> DW_AT_abstract_origin: <0x194>
<166> DW_AT_low_pc : 0x4004cb
<16e> DW_AT_high_pc : 0x9
<1><194>: Abbrev Number: 12 (DW_TAG_subprogram)
<195> DW_AT_specification: <0x109>
<199> DW_AT_inline : 3 (declared as inline and inlined)
...
The missing breakpoint location is specified by DIE 0x161, which is ignored by
the partial DIE reader because it's a child of a DW_TAG_subprogram DIE (at
0x146, for foo).
Fix this by not ignoring the DIE during partial DIE reading.
Tested on x86_64-linux.
gdb/ChangeLog:
2020-06-03 Tom de Vries <tdevries@suse.de>
PR symtab/26046
* dwarf2/read.c (scan_partial_symbols): Recurse into DW_TAG_subprogram
children for C++.
(load_partial_dies): Don't skip DW_TAG_inlined_subroutine child of
DW_TAG_subprogram.
gdb/testsuite/ChangeLog:
2020-06-03 Tom de Vries <tdevries@suse.de>
PR symtab/26046
* gdb.cp/breakpoint-locs-2.cc: New test.
* gdb.cp/breakpoint-locs.cc: New test.
* gdb.cp/breakpoint-locs.exp: New file.
* gdb.cp/breakpoint-locs.h: New test.
After the is-stmt support commit:
commit 8c95582da8
Date: Mon Dec 30 21:04:51 2019 +0000
gdb: Add support for tracking the DWARF line table is-stmt field
A regression was observed where a breakpoint could no longer be placed
in some cases.
Consider a line table like this:
File 1: test.c
File 2: test.h
| Addr | File | Line | Stmt |
|------|------|------|------|
| 1 | 1 | 16 | Y |
| 2 | 1 | 17 | Y |
| 3 | 2 | 21 | Y |
| 4 | 2 | 22 | Y |
| 4 | 1 | 18 | N |
| 5 | 2 | 23 | N |
| 6 | 1 | 24 | Y |
| 7 | 1 | END | Y |
|------|------|------|------|
Before the is-stmt patch GDB would ignore any non-stmt lines, so GDB
built two line table structures:
File 1 File 2
------ ------
| Addr | Line | | Addr | Line |
|------|------| |------|------|
| 1 | 16 | | 3 | 21 |
| 2 | 17 | | 4 | 22 |
| 3 | END | | 6 | END |
| 6 | 24 | |------|------|
| 7 | END |
|------|------|
After the is-stmt patch GDB now records non-stmt lines, so the
generated line table structures look like this:
File 1 File 2
------ ------
| Addr | Line | Stmt | | Addr | Line | Stmt |
|------|------|------| |------|------|------|
| 1 | 16 | Y | | 3 | 21 | Y |
| 2 | 17 | Y | | 4 | 22 | Y |
| 3 | END | Y | | 4 | END | Y |
| 4 | 18 | N | | 5 | 23 | N |
| 5 | END | Y | | 6 | END | Y |
| 6 | 24 | Y | |------|------|------|
| 7 | END | Y |
|------|------|------|
The problem is that in 'File 2', end END marker at address 4 causes
the previous line table entry to be discarded, so we actually end up
with this:
File 2
------
| Addr | Line | Stmt |
|------|------|------|
| 3 | 21 | Y |
| 4 | END | Y |
| 5 | 23 | N |
| 6 | END | Y |
|------|------|------|
When a user tries to place a breakpoint in file 2 at line 22, this is
no longer possible.
The solution I propose here is that we ignore line table entries that
would trigger a change of file if:
1. The new line being added is at the same address as the previous
line, and
2. We have previously seen an is-stmt line at the current address.
The result of this is that GDB switches file, and knows that some line
entry (or entries) are going to be discarded, prefer to keep is-stmt
lines and discard non-stmt lines.
After this commit the lines tables are now:
File 1 File 2
------ ------
| Addr | Line | Stmt | | Addr | Line | Stmt |
|------|------|------| |------|------|------|
| 1 | 16 | Y | | 3 | 21 | Y |
| 2 | 17 | Y | | 4 | 22 | Y |
| 3 | END | Y | | 5 | 23 | N |
| 5 | END | Y | | 6 | END | Y |
| 6 | 24 | Y | |------|------|------|
| 7 | END | Y |
|------|------|------|
We've lost the non-stmt entry for file 1, line 18, but retained the
is-stmt entry for file 2, line 22. The user can now place a
breakpoint at that location.
One problem that came from this commit was the test
gdb.cp/step-and-next-inline.exp, which broke in several places. After
looking at this test again I think that in some cases this test was
only ever passing by pure luck. The debug GCC is producing for this
test is pretty broken. I raised this GCC bug:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94474
for this and disabled one entire half of the test. There are still
some cases in here that do pass, and if/when GCC is fixed it would be
great to enable this test again.
gdb/ChangeLog:
* dwarf2/read.c (class lnp_state_machine) <m_last_address>: New
member variable.
<m_stmt_at_address>: New member variable.
(lnp_state_machine::record_line): Don't record some lines, update
tracking of is_stmt at the same address.
(lnp_state_machine::lnp_state_machine): Initialise new member
variables.
gdb/testsuite/ChangeLog:
* gdb.cp/step-and-next-inline.exp (do_test): Skip all tests in the
use_header case.
* gdb.dwarf2/dw2-inline-header-1.exp: New file.
* gdb.dwarf2/dw2-inline-header-2.exp: New file.
* gdb.dwarf2/dw2-inline-header-3.exp: New file.
* gdb.dwarf2/dw2-inline-header-lbls.c: New file.
* gdb.dwarf2/dw2-inline-header.c: New file.
* gdb.dwarf2/dw2-inline-header.h: New file.
While doing the psymtab-sharing patchset, I avoided renaming variables
unnecessarily to avoid adding noise to patches, but I'd like to do it
now. Basically, we have these dwarf2 per-something structures:
- dwarf2_per_objfile
- dwarf2_per_bfd
- dwarf2_per_cu_data
I named the instances of dwarf2_per_bfd `per_bfd` and most of instances
of dwarf2_per_cu_data are called `per_cu`. Most pre-existing instances
of dwarf2_per_objfile are named `dwarf2_per_objfile`. For consistency
with the other type, I'd like to rename them to just `per_objfile`. The
`dwarf2_` prefix is superfluous, since it's already clear we are in
dwarf2 code. It also helps reducing the line wrapping by saving 7
precious columns.
gdb/ChangeLog:
* dwarf2/comp-unit.c, dwarf2/comp-unit.h, dwarf2/index-cache.c,
dwarf2/index-cache.h, dwarf2/index-write.c,
dwarf2/index-write.h, dwarf2/line-header.c,
dwarf2/line-header.h, dwarf2/macro.c, dwarf2/macro.h,
dwarf2/read.c, dwarf2/read.h: Rename struct dwarf2_per_objfile
variables and fields from `dwarf2_per_objfile` to just
`per_objfile` throughout.
Change-Id: I3c45cdcc561265e90df82cbd36b4b4ef2fa73aef
