MatCat.OpenSource/8sa1-gcc
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

libstd++: : Add workaround for as Error: file number less than one error [PR98708]

Browse Source 
As mentioned in the PR, since the switch to DWARF5 by default instead of
DWARF4, gcc fails to build when configured against recent binutils.

The problem is that cxx11-ios_failure* is built in separate steps,
-S compilation (with -g -O2) followed by some sed and followed by
-c -g -O2 -g0 assembly.  When gcc is configured against recent binutils
and DWARF5 is the default, we emit .file 0 "..." directive on which the
assembler then fails (unless --gdwarf-5 is passed to it, but we don't want
that generally because on the other side older assemblers don't like -g*
passed to it when invoked on *.s file with compiler generated debug info.

I hope the bug will be fixed soon on the binutils side, but it would be nice
to have a workaround.

The following patch is one of the possibilities, another one is to do that
but add configure check for whether it is needed,
essentially
echo 'int main () { return 0; }' > conftest.c
${CXX} ${CXXFLAGS} -g -O2 -S conftest.c -o conftest.s
${CXX} ${CXXFLAGS} -g -O2 -g0 -c conftest.s -o conftest.o
and if the last command fails, we need that -gno-as-loc-support.
Or yet another option would be I think do a different check, whether
${CXX} ${CXXFLAGS} -g -O2 -S conftest.c -o conftest.s
${CXX} ${CXXFLAGS} -g -O2 -c conftest.s -o conftest.o
works and if yes, don't add the -g0 to cxx11-ios_failure*.s assembly.

2021-01-18  Jakub Jelinek  <jakub@redhat.com>

	PR debug/98708
	* src/c++11/Makefile.am (cxx11-ios_failure-lt.s, cxx11-ios_failure.s):
	Compile with -gno-as-loc-support.
	* src/c++11/Makefile.in: Regenerated.
This commit is contained in:
Jakub Jelinek 2021-01-18 11:28:17 +01:00
parent 0f951b3dd3
commit 2e43880dbd
2 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
libstdc++-v3/src/c++11/Makefile.am
View File

@ -141,12 +141,12 @@ if ENABLE_DUAL_ABI
rewrite_ios_failure_typeinfo = sed -e '/^_*_ZTISt13__ios_failure:/,/_ZTVN10__cxxabiv120__si_class_type_infoE/s/_ZTVN10__cxxabiv120__si_class_type_infoE/_ZTVSt19__iosfail_type_info/'
cxx11-ios_failure-lt.s: cxx11-ios_failure.cc
$(LTCXXCOMPILE) -S $< -o tmp-cxx11-ios_failure-lt.s
$(LTCXXCOMPILE) -gno-as-loc-support -S $< -o tmp-cxx11-ios_failure-lt.s
-test -f tmp-cxx11-ios_failure-lt.o && mv -f tmp-cxx11-ios_failure-lt.o tmp-cxx11-ios_failure-lt.s
$(rewrite_ios_failure_typeinfo) tmp-$@ > $@
-rm -f tmp-$@
cxx11-ios_failure.s: cxx11-ios_failure.cc
$(CXXCOMPILE) -S $< -o tmp-$@
$(CXXCOMPILE) -gno-as-loc-support -S $< -o tmp-$@
$(rewrite_ios_failure_typeinfo) tmp-$@ > $@
-rm -f tmp-$@

4
libstdc++-v3/src/c++11/Makefile.in
View File

@ -852,12 +852,12 @@ limits.o: limits.cc
$(CXXCOMPILE) -fchar8_t -c $<
@ENABLE_DUAL_ABI_TRUE@cxx11-ios_failure-lt.s: cxx11-ios_failure.cc
@ENABLE_DUAL_ABI_TRUE@ $(LTCXXCOMPILE) -S $< -o tmp-cxx11-ios_failure-lt.s
@ENABLE_DUAL_ABI_TRUE@ $(LTCXXCOMPILE) -gno-as-loc-support -S $< -o tmp-cxx11-ios_failure-lt.s
@ENABLE_DUAL_ABI_TRUE@ -test -f tmp-cxx11-ios_failure-lt.o && mv -f tmp-cxx11-ios_failure-lt.o tmp-cxx11-ios_failure-lt.s
@ENABLE_DUAL_ABI_TRUE@ $(rewrite_ios_failure_typeinfo) tmp-$@ > $@
@ENABLE_DUAL_ABI_TRUE@ -rm -f tmp-$@
@ENABLE_DUAL_ABI_TRUE@cxx11-ios_failure.s: cxx11-ios_failure.cc
@ENABLE_DUAL_ABI_TRUE@ $(CXXCOMPILE) -S $< -o tmp-$@
@ENABLE_DUAL_ABI_TRUE@ $(CXXCOMPILE) -gno-as-loc-support -S $< -o tmp-$@
@ENABLE_DUAL_ABI_TRUE@ $(rewrite_ios_failure_typeinfo) tmp-$@ > $@
@ENABLE_DUAL_ABI_TRUE@ -rm -f tmp-$@