gcc -O2 -g -o ar -Wl,--as-needed arparse.o arlex.o ar.o not-ranlib.o arsup.o rename.o binemul.o emul_vanilla.o bucomm.o version.o filemode.o libbfd-2.35-3.fc33.so libiberty.a -Wl,-R,.
All of the above .o files are lto, leading to libbfd-2.35-3.fc33.so
not being found needed when loading the IR objects. That's problem
number one: We exclude IR references when deciding a shared library
is needed. See PR15146. Thus none of the libbfd.so symbols are
loaded before libiberty.a is scanned, and libbfd.so contains copies of
libiberty.a functions. We ought to be using the libbfd.so copies
rather than extracting them from the archive (an object is extracted
even to satisfy IR symbols). After lto recompilation, libbfd.so is of
course found to be needed and loaded. But that causes more problems.
The lto recompilation didn't see symbol references from libbfd.so and
variables like _xexit_cleanup are made local in the recompiled
objects. Oops, two copies of them. Finally, those silly undefined
symbols in the lto output debug files, combined with definitions in
both libbfd.so and IR objects result in IR symbols being made
dynamic.
The main fix here is to revert the PR15146 change to
elf_link_add_object_symbols.
PR 26314
* elflink.c (bfd_elf_link_record_dynamic_symbol): Don't allow
IR symbols to become dynamic.
(elf_link_add_object_symbols): Don't exclude IR symbols when
deciding whether an as-needed shared library is needed.
BFD is an object file library. It permits applications to use the
same routines to process object files regardless of their format.
BFD is used by the GNU debugger, assembler, linker, and the binary
utilities.
The documentation on using BFD is scanty and may be occasionally
incorrect. Pointers to documentation problems, or an entirely
rewritten manual, would be appreciated.
There is some BFD internals documentation in doc/bfdint.texi which may
help programmers who want to modify BFD.
BFD is normally built as part of another package. See the build
instructions for that package, probably in a README file in the
appropriate directory.
BFD supports the following configure options:
--target=TARGET
The default target for which to build the library. TARGET is
a configuration target triplet, such as sparc-sun-solaris.
--enable-targets=TARGET,TARGET,TARGET...
Additional targets the library should support. To include
support for all known targets, use --enable-targets=all.
--enable-64-bit-bfd
Include support for 64 bit targets. This is automatically
turned on if you explicitly request a 64 bit target, but not
for --enable-targets=all. This requires a compiler with a 64
bit integer type, such as gcc.
--enable-shared
Build BFD as a shared library.
--with-mmap
Use mmap when accessing files. This is faster on some hosts,
but slower on others. It may not work on all hosts.
Report bugs with BFD to bug-binutils@gnu.org.
Patches are encouraged. When sending patches, always send the output
of diff -u or diff -c from the original file to the new file. Do not
send default diff output. Do not make the diff from the new file to
the original file. Remember that any patch must not break other
systems. Remember that BFD must support cross compilation from any
host to any target, so patches which use ``#ifdef HOST'' are not
acceptable. Please also read the ``Reporting Bugs'' section of the
gcc manual.
Bug reports without patches will be remembered, but they may never get
fixed until somebody volunteers to fix them.
Copyright (C) 2012-2020 Free Software Foundation, Inc.
Copying and distribution of this file, with or without modification,
are permitted in any medium without royalty provided the copyright
notice and this notice are preserved.
Alan Modra
a896df97b9