binutils-gdb/bfd
Alan Modra 5b9d7a9a64 Fix __bss_start assertion failure in _bfd_elf_fix_symbol_flags
> Building LLVM 6.0 on FreeBSD/powerpc (devel/llvm60 port) the assertion
> in the subject trips (displays twice) when linking libLTO.so.1.  The
> issue has been filed in FreeBSD's bugzilla, at
> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=237068 .  It appears
> the 'llvm::hashing::detail::get_execution_seed()::seed@@JL_LLVM_6.0'
> symbol is being weakly aliased to an indirect symbol
> __bss_start@@JL_LLVM_6.0.  Since __bss_start@@JL_LLVM_6.0 is an
> indirect symbol, it fails the assertion.

I haven't looked under a debugger at your testcase but I think I know
what is going on here.  You have a shared library with a weakly
defined llvm::hashing::detail::get_execution_seed()::seed which
happens to be at the same location as __bss_start in that library.  At
the time the linker loads symbols for that library, it sees they are
both versioned and thus introduces non-versioned indirect symbols for
them.  The linker considers the symbols as possibly being aliases,
setting up h->u.alias and h->is_weakalias such that
__bss_start@@JL_LLVM_6.0 is the definition.  No real problem so far,
the definition is bfd_link_hash_defined, except that the zero size, no
type __bss_start symbol possibly should not be considered an alias in
the first place.

Later, __bss_start as defined by the linker script is entered into the
linker symbol table.  This is similar to __bss_start being defined by
a regular object file in that ELF symbol resolution rules say that the
value of __bss_start in the library is overridden by __bss_start in
the executable/library being produced.  So to accomplish the override,
ld flips __bss_start from being an indirect symbol pointing at
__bss_start@@JL_LLVM_6.0 to __bss_start@@JL_LLVM_6.0 being an indirect
symbol pointing at __bss_start.  That's how we get an unexpected
indirect symbol and hit the assert.

What should happen I think, is for the def->def_regular code above the
assert to run in this case.  The symbols are no longer aliases.

	* elflink.c (_bfd_elf_fix_symbol_flags): If the def for an
	alias is no longer bfd_link_hash_defined, clear the alias.
2019-07-15 16:02:42 +09:30
..
doc
hosts
po Regen POTFILES for bpf 2019-05-24 23:15:07 +09:30
.gitignore
acinclude.m4
aclocal.m4
aix5ppc-core.c
aix386-core.c
aout32.c
aout64.c
aout-cris.c
aout-ns32k.c
aout-target.h
aout-tic30.c Obsolete tic30-aout, and linker segmentation faults 2019-05-28 10:55:21 +09:30
aoutx.h
arc-got.h
arc-plt.def
arc-plt.h
archive64.c
archive.c
archures.c bfd: add support for eBPF 2019-05-23 19:33:41 +02:00
bfd-in2.h [LD, AArch64] Move ELF options behind -z 2019-06-06 12:21:14 +01:00
bfd-in.h [LD, AArch64] Move ELF options behind -z 2019-06-06 12:21:14 +01:00
bfd.c
bfd.m4
bfdio.c
bfdwin.c
binary.c
cache.c
cf-i386lynx.c
ChangeLog Fix __bss_start assertion failure in _bfd_elf_fix_symbol_flags 2019-07-15 16:02:42 +09:30
ChangeLog-0001
ChangeLog-0203
ChangeLog-2004
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ChangeLog-2006
ChangeLog-2007
ChangeLog-2008
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ChangeLog-2010
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ChangeLog-2013
ChangeLog-2014
ChangeLog-2015
ChangeLog-2016
ChangeLog-2017
ChangeLog-2018
ChangeLog-9193
ChangeLog-9495
ChangeLog-9697
ChangeLog-9899
cisco-core.c
coff64-rs6000.c
coff-alpha.c
coff-arm.c
coff-bfd.c
coff-bfd.h
coff-go32.c
coff-i386.c
coff-ia64.c
coff-mcore.c
coff-mips.c
coff-ppc.c
coff-rs6000.c
coff-sh.c
coff-stgo32.c
coff-tic4x.c
coff-tic30.c
coff-tic54x.c
coff-tic80.c
coff-x86_64.c
coff-z8k.c
coff-z80.c
coffcode.h
coffgen.c
cofflink.c COFF linker segmentation faults 2019-05-28 17:57:51 +09:30
coffswap.h
compress.c Fix a bug recently introduced to the linker where it would complain about a section being larger than a file, even if the section was artificial. 2019-07-02 14:14:13 +01:00
config.bfd Plugin target handling 2019-06-28 10:18:49 +09:30
config.in
configure Plugin target handling 2019-06-28 10:18:49 +09:30
configure.ac Plugin target handling 2019-06-28 10:18:49 +09:30
configure.com
configure.host
COPYING
corefile.c
cpu-aarch64.c
cpu-alpha.c
cpu-arc.c
cpu-arm.c
cpu-avr.c
cpu-bfin.c
cpu-bpf.c bfd: add support for eBPF 2019-05-23 19:33:41 +02:00
cpu-cr16.c
cpu-cr16c.c
cpu-cris.c
cpu-crx.c
cpu-csky.c
cpu-d10v.c
cpu-d30v.c
cpu-dlx.c
cpu-epiphany.c
cpu-fr30.c
cpu-frv.c
cpu-ft32.c
cpu-h8300.c
cpu-hppa.c
cpu-i386.c
cpu-ia64-opc.c
cpu-ia64.c
cpu-iamcu.c
cpu-ip2k.c
cpu-iq2000.c
cpu-k1om.c
cpu-l1om.c
cpu-lm32.c
cpu-m9s12x.c
cpu-m9s12xg.c
cpu-m32c.c
cpu-m32r.c
cpu-m68hc11.c
cpu-m68hc12.c
cpu-m68k.c
cpu-m10200.c
cpu-m10300.c
cpu-mcore.c
cpu-mep.c
cpu-metag.c
cpu-microblaze.c
cpu-mips.c
cpu-mmix.c
cpu-moxie.c
cpu-msp430.c
cpu-mt.c
cpu-nds32.c
cpu-nfp.c
cpu-nios2.c
cpu-ns32k.c
cpu-or1k.c
cpu-pdp11.c
cpu-pj.c
cpu-plugin.c
cpu-powerpc.c
cpu-pru.c
cpu-riscv.c
cpu-rl78.c
cpu-rs6000.c
cpu-rx.c
cpu-s12z.c
cpu-s390.c
cpu-score.c
cpu-sh.c
cpu-sparc.c
cpu-spu.c
cpu-tic4x.c
cpu-tic6x.c
cpu-tic30.c
cpu-tic54x.c
cpu-tic80.c
cpu-tilegx.c
cpu-tilepro.c
cpu-v850_rh850.c
cpu-v850.c
cpu-vax.c
cpu-visium.c
cpu-wasm32.c
cpu-xc16x.c
cpu-xgate.c
cpu-xstormy16.c
cpu-xtensa.c
cpu-z8k.c
cpu-z80.c
dep-in.sed
development.sh
dwarf1.c
dwarf2.c XCOFF linker segmentation fault 2019-05-28 10:05:02 +09:30
ecoff.c
ecofflink.c
ecoffswap.h
elf32-am33lin.c
elf32-arc.c
elf32-arm.c PR ld/24709 [arm] linker crash and assertion failure with CMSE 2019-07-02 13:09:02 +00:00
elf32-avr.c Fix PR 24571 - Relaxation does not shorten jmp or call to target at pc-relative range boundary 2019-05-21 12:48:06 +05:30
elf32-avr.h
elf32-bfin.c
elf32-cr16.c
elf32-cr16c.c
elf32-cris.c
elf32-crx.c
elf32-csky.c
elf32-d10v.c
elf32-d30v.c
elf32-dlx.c
elf32-dlx.h
elf32-epiphany.c
elf32-fr30.c
elf32-frv.c
elf32-ft32.c
elf32-gen.c
elf32-h8300.c
elf32-hppa.c
elf32-hppa.h
elf32-i386.c
elf32-ip2k.c
elf32-iq2000.c
elf32-lm32.c LM32 linker segmentation faults 2019-05-28 14:38:31 +09:30
elf32-m32c.c
elf32-m32r.c
elf32-m68hc1x.c
elf32-m68hc1x.h
elf32-m68hc11.c
elf32-m68hc12.c
elf32-m68k.c m68k linker segmentation faults 2019-05-28 14:38:08 +09:30
elf32-mcore.c
elf32-mep.c
elf32-metag.c
elf32-metag.h
elf32-microblaze.c Microblaze linker segmentation fault 2019-05-28 15:56:14 +09:30
elf32-mips.c
elf32-moxie.c
elf32-msp430.c
elf32-mt.c
elf32-nds32.c
elf32-nds32.h
elf32-nios2.c
elf32-nios2.h
elf32-or1k.c
elf32-pj.c PicoJava weak undefined symbols 2019-05-06 11:41:28 +09:30
elf32-ppc.c Dynamic TLS section symbols 2019-07-13 09:57:50 +09:30
elf32-ppc.h
elf32-pru.c
elf32-rl78.c
elf32-rx.c
elf32-rx.h
elf32-s12z.c
elf32-s390.c
elf32-score7.c
elf32-score.c
elf32-score.h
elf32-sh-relocs.h
elf32-sh.c
elf32-sparc.c
elf32-spu.c
elf32-spu.h
elf32-tic6x.c
elf32-tic6x.h
elf32-tilegx.c
elf32-tilegx.h
elf32-tilepro.c
elf32-tilepro.h
elf32-v850.c
elf32-vax.c
elf32-visium.c
elf32-wasm32.c
elf32-xc16x.c
elf32-xgate.c
elf32-xstormy16.c
elf32-xtensa.c
elf32.c
elf64-alpha.c Alpha-linux linker segmentation fault 2019-05-28 15:11:54 +09:30
elf64-bpf.c bfd: add support for eBPF 2019-05-23 19:33:41 +02:00
elf64-gen.c
elf64-hppa.c HPPA64 linker segmentation faults 2019-05-28 10:55:41 +09:30
elf64-hppa.h
elf64-ia64-vms.c
elf64-mips.c
elf64-mmix.c
elf64-nfp.c
elf64-ppc.c Dynamic TLS section symbols 2019-07-13 09:57:50 +09:30
elf64-ppc.h
elf64-s390.c
elf64-sparc.c
elf64-tilegx.c
elf64-tilegx.h
elf64-x86-64.c
elf64.c
elf-attrs.c
elf-bfd.h Stop the BFD library from issuing a warning message when processing allocated sections in debuginfo files that lie outside of any loadable segment. 2019-07-02 15:58:29 +01:00
elf-eh-frame.c
elf-hppa.h
elf-ifunc.c
elf-linker-x86.h
elf-linux-core.h
elf-m10200.c
elf-m10300.c
elf-nacl.c
elf-nacl.h
elf-properties.c bfd/elf-properties: avoid shadowing a C library symbol 2019-06-25 12:01:50 +02:00
elf-s390-common.c
elf-s390.h
elf-strtab.c
elf-vxworks.c
elf-vxworks.h
elf.c Stop the BFD library from issuing a warning message when processing allocated sections in debuginfo files that lie outside of any loadable segment. 2019-07-02 15:58:29 +01:00
elfcode.h PR24689 again, string table corruption 2019-06-23 14:24:45 +09:30
elfcore.h
elflink.c Fix __bss_start assertion failure in _bfd_elf_fix_symbol_flags 2019-07-15 16:02:42 +09:30
elfn32-mips.c
elfnn-aarch64.c aarch64: remove unnecessary loc_hash_table traversal 2019-06-17 17:58:53 +01:00
elfnn-ia64.c
elfnn-riscv.c RISC-V: Enable lui relaxation for CODE and MERGE sections. 2019-06-24 13:50:10 -07:00
elfxx-aarch64.c [BFD, AArch64] Fix PT_GNU_PROPERTY alignment issue 2019-06-06 12:27:41 +01:00
elfxx-aarch64.h
elfxx-ia64.c
elfxx-ia64.h
elfxx-mips.c MIPS/LD: Skip overflow check for %pcrel_hi relocations 2019-05-28 10:49:16 -07:00
elfxx-mips.h [MIPS] Add generation of PLT entries with compact jumps for MIPS R6 2019-05-21 09:22:28 -07:00
elfxx-riscv.c
elfxx-riscv.h
elfxx-sparc.c
elfxx-sparc.h
elfxx-target.h
elfxx-tilegx.c
elfxx-tilegx.h
elfxx-x86.c
elfxx-x86.h
format.c Plugin target handling 2019-06-28 10:18:49 +09:30
gen-aout.c
genlink.h
go32stub.h
hash.c
host-aout.c
hppabsd-core.c
hpux-core.c
i386aout.c
i386bsd.c
i386lynx.c
i386msdos.c
ihex.c
init.c
irix-core.c
libaout.h
libbfd-in.h
libbfd.c
libbfd.h PowerPC relocations for prefix insns 2019-05-24 10:27:49 +09:30
libcoff-in.h
libcoff.h
libecoff.h
libhppa.h
libpei.h
libxcoff.h
linker.c Generic ELF target group signature symbol 2019-05-27 13:56:28 +09:30
lynx-core.c
mach-o-aarch64.c
mach-o-arm.c Ensure that when attempting to process an ARM Mach-O file with unknown relocs, that a suitable error message is displayed. 2019-06-26 17:03:32 +01:00
mach-o-i386.c
mach-o-target.c
mach-o-x86-64.c
mach-o.c Ensure that when attempting to process an ARM Mach-O file with unknown relocs, that a suitable error message is displayed. 2019-06-26 17:03:32 +01:00
mach-o.h
MAINTAINERS
Makefile.am bfd: add support for eBPF 2019-05-23 19:33:41 +02:00
Makefile.in Regenerate with approved autotools version 2019-06-14 10:30:35 +09:30
makefile.vms
mep-relocs.pl
merge.c
mmo.c
netbsd-core.c
netbsd.h
ns32k.h
ns32knetbsd.c
opncls.c
osf-core.c
pc532-mach.c
pdp11.c
pe-arm-wince.c
pe-arm.c
pe-i386.c
pe-mcore.c
pe-ppc.c
pe-sh.c
pe-x86_64.c
pef-traceback.h
pef.c
pef.h
pei-arm-wince.c
pei-arm.c
pei-i386.c
pei-ia64.c
pei-mcore.c
pei-ppc.c
pei-sh.c
pei-x86_64.c
peicode.h
peXXigen.c
plugin.c
plugin.h
PORTING
ppcboot.c
ptrace-core.c
README
reloc16.c
reloc.c PowerPC relocations for prefix insns 2019-05-24 10:27:49 +09:30
rs6000-core.c
sco5-core.c
section.c
simple.c
som.c bfdtest1 segfaults on hppa-hp-hpux10 2019-05-22 18:33:39 +09:30
som.h
srec.c
stab-syms.c
stabs.c
stamp-h.in
syms.c
sysdep.h
targets.c Plugin target handling 2019-06-28 10:18:49 +09:30
targmatch.sed
tekhex.c
TODO
trad-core.c
vax1knetbsd.c
vaxnetbsd.c
verilog.c Add new option to objcopy: --verilog-data-width. Use this option to set the size of byte bundles generated in verilog format files. 2019-05-14 10:42:25 +01:00
version.h Automatic date update in version.in 2019-07-15 00:00:42 +00:00
version.m4
vms-alpha.c vms-alpha gas segfault 2019-05-22 18:33:39 +09:30
vms-lib.c
vms-misc.c
vms.h
warning.m4
wasm-module.c
wasm-module.h
xcofflink.c XCOFF linker segmentation fault 2019-05-28 10:05:02 +09:30
xsym.c
xsym.h
xtensa-isa.c
xtensa-modules.c

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BFD is an object file library.  It permits applications to use the
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BFD is used by the GNU debugger, assembler, linker, and the binary
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