gcc/libiberty
Jakub Jelinek bb8dd0980b libiberty: Fix up > 64K section handling in simple_object_elf_copy_lto_debug_section [PR116614]
cat abc.C
  #define A(n) struct T##n {} t##n;
  #define B(n) A(n##0) A(n##1) A(n##2) A(n##3) A(n##4) A(n##5) A(n##6) A(n##7) A(n##8) A(n##9)
  #define C(n) B(n##0) B(n##1) B(n##2) B(n##3) B(n##4) B(n##5) B(n##6) B(n##7) B(n##8) B(n##9)
  #define D(n) C(n##0) C(n##1) C(n##2) C(n##3) C(n##4) C(n##5) C(n##6) C(n##7) C(n##8) C(n##9)
  #define E(n) D(n##0) D(n##1) D(n##2) D(n##3) D(n##4) D(n##5) D(n##6) D(n##7) D(n##8) D(n##9)
  E(1) E(2) E(3)
  int main () { return 0; }
./xg++ -B ./ -o abc{.o,.C} -flto -flto-partition=1to1 -O2 -g -fdebug-types-section -c
./xgcc -B ./ -o abc{,.o} -flto -flto-partition=1to1 -O2
(not included in testsuite as it takes a while to compile) FAILs with
lto-wrapper: fatal error: Too many copied sections: Operation not supported
compilation terminated.
/usr/bin/ld: error: lto-wrapper failed
collect2: error: ld returned 1 exit status

The following patch fixes that.  Most of the 64K+ section support for
reading and writing was already there years ago (and especially reading used
quite often already) and a further bug fixed in it in the PR104617 fix.

Yet, the fix isn't solely about removing the
  if (new_i - 1 >= SHN_LORESERVE)
    {
      *err = ENOTSUP;
      return "Too many copied sections";
    }
5 lines, the missing part was that the function only handled reading of
the .symtab_shndx section but not copying/updating of it.
If the result has less than 64K-epsilon sections, that actually wasn't
needed, but e.g. with -fdebug-types-section one can exceed that pretty
easily (reported to us on WebKitGtk build on ppc64le).
Updating the section is slightly more complicated, because it basically
needs to be done in lock step with updating the .symtab section, if one
doesn't need to use SHN_XINDEX in there, the section should (or should be
updated to) contain SHN_UNDEF entry, otherwise needs to have whatever would
be overwise stored but couldn't fit.  But repeating due to that all the
symtab decisions what to discard and how to rewrite it would be ugly.

So, the patch instead emits the .symtab_shndx section (or sections) last
and prepares the content during the .symtab processing and in a second
pass when going just through .symtab_shndx sections just uses the saved
content.

2024-09-07  Jakub Jelinek  <jakub@redhat.com>

	PR lto/116614
	* simple-object-elf.c (SHN_COMMON): Align comment with neighbouring
	comments.
	(SHN_HIRESERVE): Use uppercase hex digits instead of lowercase for
	consistency.
	(simple_object_elf_find_sections): Formatting fixes.
	(simple_object_elf_fetch_attributes): Likewise.
	(simple_object_elf_attributes_merge): Likewise.
	(simple_object_elf_start_write): Likewise.
	(simple_object_elf_write_ehdr): Likewise.
	(simple_object_elf_write_shdr): Likewise.
	(simple_object_elf_write_to_file): Likewise.
	(simple_object_elf_copy_lto_debug_section): Likewise.  Don't fail for
	new_i - 1 >= SHN_LORESERVE, instead arrange in that case to copy
	over .symtab_shndx sections, though emit those last and compute their
	section content when processing associated .symtab sections.  Handle
	simple_object_internal_read failure even in the .symtab_shndx reading
	case.
2024-09-07 09:39:06 +02:00
..
config
testsuite libiberty/buildargv: handle input consisting of only white space 2024-07-16 13:52:03 +01:00
_doprnt.c Update copyright years. 2024-01-03 12:19:35 +01:00
.gitignore
acinclude.m4 Update copyright years. 2024-01-03 12:19:35 +01:00
aclocal.m4 libiberty: Disable hwcaps for sha1.o 2023-11-30 10:06:23 +01:00
alloca.c
argv.c libiberty/argv.c: remove only_whitespace 2024-08-05 12:35:38 +01:00
asprintf.c Update copyright years. 2024-01-03 12:19:35 +01:00
at-file.texi
atexit.c
basename.c
bcmp.c
bcopy.c
bsearch_r.c
bsearch.c
bzero.c
calloc.c
ChangeLog Daily bump. 2024-08-06 00:17:19 +00:00
ChangeLog.jit
choose-temp.c Update copyright years. 2024-01-03 12:19:35 +01:00
clock.c Update copyright years. 2024-01-03 12:19:35 +01:00
concat.c Update copyright years. 2024-01-03 12:19:35 +01:00
config.h-vms
config.in libiberty: Use x86 HW optimized sha1 2023-11-28 13:14:05 +01:00
configure libiberty: Fix build with GCC < 7 2023-12-05 23:32:19 +01:00
configure.ac libiberty: Fix build with GCC < 7 2023-12-05 23:32:19 +01:00
configure.com
copying-lib.texi Update copyright years. 2024-01-03 12:19:35 +01:00
COPYING.LIB
copysign.c
cp-demangle.c c++, demangle: Implement https://github.com/itanium-cxx-abi/cxx-abi/issues/148 non-proposal 2024-01-13 10:23:53 +01:00
cp-demangle.h Update copyright years. 2024-01-03 12:19:35 +01:00
cp-demint.c Update copyright years. 2024-01-03 12:19:35 +01:00
cplus-dem.c libiberty: Invoke D demangler when --format=auto 2024-04-02 13:30:19 -06:00
crc32.c Update copyright years. 2024-01-03 12:19:35 +01:00
d-demangle.c Update copyright years. 2024-01-03 12:19:35 +01:00
dwarfnames.c Update copyright years. 2024-01-03 12:19:35 +01:00
dyn-string.c Fix up duplicated words mostly in comments, part 1 2024-04-02 13:39:11 +02:00
fdmatch.c Update copyright years. 2024-01-03 12:19:35 +01:00
ffs.c
fibheap.c Update copyright years. 2024-01-03 12:19:35 +01:00
filedescriptor.c Update copyright years. 2024-01-03 12:19:35 +01:00
filename_cmp.c Update copyright years. 2024-01-03 12:19:35 +01:00
floatformat.c Update copyright years. 2024-01-03 12:19:35 +01:00
fnmatch.c Update copyright years. 2024-01-03 12:19:35 +01:00
fnmatch.txh
fopen_unlocked.c Update copyright years. 2024-01-03 12:19:35 +01:00
functions.texi
gather-docs Update copyright years. 2024-01-03 12:19:35 +01:00
getcwd.c
getopt1.c Update copyright years. 2024-01-03 12:19:35 +01:00
getopt.c Update copyright years. 2024-01-03 12:19:35 +01:00
getpagesize.c
getpwd.c
getruntime.c Update copyright years. 2024-01-03 12:19:35 +01:00
gettimeofday.c
hashtab.c [libiberty] remove TBAA violation in iterative_hash, improve code-gen 2024-02-15 09:14:22 +01:00
hex.c Update copyright years. 2024-01-03 12:19:35 +01:00
index.c
insque.c
lbasename.c Update copyright years. 2024-01-03 12:19:35 +01:00
libiberty.texi Update copyright years. 2024-01-03 12:19:35 +01:00
lrealpath.c Update copyright years. 2024-01-03 12:19:35 +01:00
maint-tool Update copyright years. 2024-01-03 12:19:35 +01:00
make-relative-prefix.c Update copyright years. 2024-01-03 12:19:35 +01:00
make-temp-file.c Update copyright years. 2024-01-03 12:19:35 +01:00
Makefile.in Update copyright years. 2024-01-03 12:19:35 +01:00
makefile.vms
md5.c Update copyright years. 2024-01-03 12:19:35 +01:00
memchr.c
memcmp.c
memcpy.c
memmem.c Update copyright years. 2024-01-03 12:19:35 +01:00
memmove.c
mempcpy.c Update copyright years. 2024-01-03 12:19:35 +01:00
memset.c
mkstemps.c Update copyright years. 2024-01-03 12:19:35 +01:00
msdos.c
objalloc.c Update copyright years. 2024-01-03 12:19:35 +01:00
obstack.c Update copyright years. 2024-01-03 12:19:35 +01:00
obstacks.texi
partition.c Update copyright years. 2024-01-03 12:19:35 +01:00
pex-common.c Update copyright years. 2024-01-03 12:19:35 +01:00
pex-common.h Update copyright years. 2024-01-03 12:19:35 +01:00
pex-djgpp.c Update copyright years. 2024-01-03 12:19:35 +01:00
pex-msdos.c Update copyright years. 2024-01-03 12:19:35 +01:00
pex-one.c Update copyright years. 2024-01-03 12:19:35 +01:00
pex-unix.c libiberty: Fix error return value in pex_unix_exec_child [PR113957]. 2024-02-19 20:13:30 +00:00
pex-win32.c Update copyright years. 2024-01-03 12:19:35 +01:00
pexecute.c Update copyright years. 2024-01-03 12:19:35 +01:00
pexecute.txh
physmem.c Update copyright years. 2024-01-03 12:19:35 +01:00
putenv.c Update copyright years. 2024-01-03 12:19:35 +01:00
random.c
README
regex.c Fix up duplicated words mostly in comments, part 1 2024-04-02 13:39:11 +02:00
rename.c
rindex.c
rust-demangle.c Update copyright years. 2024-01-03 12:19:35 +01:00
safe-ctype.c Update copyright years. 2024-01-03 12:19:35 +01:00
setenv.c Update copyright years. 2024-01-03 12:19:35 +01:00
setproctitle.c Update copyright years. 2024-01-03 12:19:35 +01:00
sha1.c Update copyright years. 2024-01-03 12:19:35 +01:00
sigsetmask.c
simple-object-coff.c Update copyright years. 2024-01-03 12:19:35 +01:00
simple-object-common.h Update copyright years. 2024-01-03 12:19:35 +01:00
simple-object-elf.c libiberty: Fix up > 64K section handling in simple_object_elf_copy_lto_debug_section [PR116614] 2024-09-07 09:39:06 +02:00
simple-object-mach-o.c Update copyright years. 2024-01-03 12:19:35 +01:00
simple-object-xcoff.c Update copyright years. 2024-01-03 12:19:35 +01:00
simple-object.c Update copyright years. 2024-01-03 12:19:35 +01:00
simple-object.txh
snprintf.c Update copyright years. 2024-01-03 12:19:35 +01:00
sort.c Update copyright years. 2024-01-03 12:19:35 +01:00
spaces.c Update copyright years. 2024-01-03 12:19:35 +01:00
splay-tree.c Update copyright years. 2024-01-03 12:19:35 +01:00
stack-limit.c Update copyright years. 2024-01-03 12:19:35 +01:00
stpcpy.c Update copyright years. 2024-01-03 12:19:35 +01:00
stpncpy.c Update copyright years. 2024-01-03 12:19:35 +01:00
strcasecmp.c
strchr.c
strdup.c
strerror.c
strncasecmp.c
strncmp.c
strndup.c Update copyright years. 2024-01-03 12:19:35 +01:00
strnlen.c
strrchr.c
strsignal.c
strstr.c
strtod.c Update copyright years. 2024-01-03 12:19:35 +01:00
strtol.c
strtoll.c
strtoul.c
strtoull.c
strverscmp.c Update copyright years. 2024-01-03 12:19:35 +01:00
timeval-utils.c Update copyright years. 2024-01-03 12:19:35 +01:00
tmpnam.c
unlink-if-ordinary.c Update copyright years. 2024-01-03 12:19:35 +01:00
vasprintf.c Update copyright years. 2024-01-03 12:19:35 +01:00
vfork.c
vfprintf.c Update copyright years. 2024-01-03 12:19:35 +01:00
vprintf-support.c libiberty: Fix up libiberty_vprintf_buffer_size 2024-02-12 18:50:16 +01:00
vprintf-support.h Update copyright years. 2024-01-03 12:19:35 +01:00
vprintf.c
vsnprintf.c Update copyright years. 2024-01-03 12:19:35 +01:00
vsprintf.c Update copyright years. 2024-01-03 12:19:35 +01:00
waitpid.c
xasprintf.c Update copyright years. 2024-01-03 12:19:35 +01:00
xatexit.c
xexit.c Update copyright years. 2024-01-03 12:19:35 +01:00
xmalloc.c Update copyright years. 2024-01-03 12:19:35 +01:00
xmemdup.c
xstrdup.c
xstrerror.c
xstrndup.c Update copyright years. 2024-01-03 12:19:35 +01:00
xvasprintf.c Update copyright years. 2024-01-03 12:19:35 +01:00

This directory contains the -liberty library of free software.
It is a collection of subroutines used by various GNU programs.
Current members include:

	getopt -- get options from command line
	obstack -- stacks of arbitrarily-sized objects
	strerror -- error message strings corresponding to errno
	strtol -- string-to-long conversion
	strtoul -- string-to-unsigned-long conversion

We expect many of the GNU subroutines that are floating around to
eventually arrive here.

The library must be configured from the top source directory.  Don't
try to run configure in this directory.  Follow the configuration
instructions in ../README.

Please report bugs to https://gcc.gnu.org/bugzilla/ and send fixes to
"gcc-patches@gcc.gnu.org".  Thank you.

ADDING A NEW FILE
=================

There are two sets of files:  Those that are "required" will be
included in the library for all configurations, while those
that are "optional" will be included in the library only if "needed."

To add a new required file, edit Makefile.in to add the source file
name to CFILES and the object file to REQUIRED_OFILES.

To add a new optional file, it must provide a single function, and the
name of the function must be the same as the name of the file.

    * Add the source file name to CFILES in Makefile.in and the object
      file to CONFIGURED_OFILES.

    * Add the function to name to the funcs shell variable in
      configure.ac.

    * Add the function to the AC_CHECK_FUNCS lists just after the
      setting of the funcs shell variable.  These AC_CHECK_FUNCS calls
      are never executed; they are there to make autoheader work
      better.

    * Consider the special cases of building libiberty; as of this
      writing, the special cases are newlib and VxWorks.  If a
      particular special case provides the function, you do not need
      to do anything.  If it does not provide the function, add the
      object file to LIBOBJS, and add the function name to the case
      controlling whether to define HAVE_func.

Finally, in the build directory of libiberty, configure with
"--enable-maintainer-mode", run "make maint-deps" to update
Makefile.in, and run 'make stamp-functions' to regenerate
functions.texi.

The optional file you've added (e.g. getcwd.c) should compile and work
on all hosts where it is needed.  It does not have to work or even
compile on hosts where it is not needed.

ADDING A NEW CONFIGURATION
==========================

On most hosts you should be able to use the scheme for automatically
figuring out which files are needed.  In that case, you probably
don't need a special Makefile stub for that configuration.

If the fully automatic scheme doesn't work, you may be able to get
by with defining EXTRA_OFILES in your Makefile stub.  This is
a list of object file names that should be treated as required
for this configuration - they will be included in libiberty.a,
regardless of whatever might be in the C library.