[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 Jakub Jelinek changed: What|Removed |Added Status|NEW |RESOLVED Resolution|--- |FIXED --- Comment #18 from Jakub Jelinek --- Worked around on the gcc side and fixed on the binutils side.
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708
--- Comment #17 from CVS Commits ---
The master branch has been updated by Jakub Jelinek :
https://gcc.gnu.org/g:2e43880dbd4cb9722ae99708c01c399f985dc7c3
commit r11-6765-g2e43880dbd4cb9722ae99708c01c399f985dc7c3
Author: Jakub Jelinek
Date: Mon Jan 18 11:28:17 2021 +0100
libstd++: : Add workaround for as Error: file number less than one error
[PR98708]
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
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.
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 --- Comment #16 from Jakub Jelinek --- And the temporary workaround could be --- libstdc++-v3/src/c++11/Makefile.am.jj 2021-01-04 10:26:02.067970728 +0100 +++ libstdc++-v3/src/c++11/Makefile.am 2021-01-17 17:20:58.580262364 +0100 @@ -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 $< -o tmp-$@ $(rewrite_ios_failure_typeinfo) tmp-$@ > $@ -rm -f tmp-$@ --- libstdc++-v3/src/c++11/Makefile.in.jj 2020-12-17 02:29:28.734557483 +0100 +++ libstdc++-v3/src/c++11/Makefile.in 2021-01-17 17:21:27.510931383 +0100 @@ -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@ $(rewrite_ios_failure_typeinfo) tmp-$@ > $@ @ENABLE_DUAL_ABI_TRUE@ -rm -f tmp-$@
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 --- Comment #15 from Jakub Jelinek --- Comment on attachment 49986 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=49986 A patch If that works, that would be great. I can't easily test it right away, but perhaps you could. Just compile some other libstdc++ source with -g -O2 -c on gcc configured against latest binutils, save the *.o file and repeat with -g -O2 -S + assembly by hand without -g* and compare if the readelf -wl between the two is identical.
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 --- Comment #14 from H.J. Lu --- Created attachment 49986 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=49986=edit A patch How about this assembler patch?
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 --- Comment #13 from Jakub Jelinek --- But then it will warn and not do what it was expected to do. Anyway, I've rebuilt cc1plus (on a box without new binutils) with hacking up auto-host.h so that it normally emits .file 0 "..." directive, and with -gno-as-loc-support it doesn't emit it. Will try it soon in a koji build where it failed.
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708
--- Comment #12 from Mark Wielaard ---
On the binutils gas side it could be as simple as turning the error into a
warning:
diff --git a/gas/dwarf2dbg.c b/gas/dwarf2dbg.c
index a428370ecca..a216bfd6b28 100644
--- a/gas/dwarf2dbg.c
+++ b/gas/dwarf2dbg.c
@@ -1044,7 +1044,7 @@ dwarf2_directive_filename (void)
if ((offsetT) num < 1 && DWARF2_LINE_VERSION < 5)
{
- as_bad (_("file number less than one"));
+ as_warn (_("file number less than one, ignored"));
ignore_rest_of_line ();
return NULL;
}
@@ -1143,7 +1143,8 @@ dwarf2_directive_loc (int dummy ATTRIBUTE_UNUSED)
{
if (filenum != 0 || DWARF2_LINE_VERSION < 5)
{
- as_bad (_("file number less than one"));
+ as_warn (_("file number less than one, ignored"));
+ ignore_rest_of_line ();
return;
}
}
diff --git a/gas/testsuite/gas/lns/lns-diag-1.l
b/gas/testsuite/gas/lns/lns-diag-1.l
index 1256e85cfcb..d8aa84d9d1a 100644
--- a/gas/testsuite/gas/lns/lns-diag-1.l
+++ b/gas/testsuite/gas/lns/lns-diag-1.l
@@ -1,5 +1,5 @@
.*: Assembler messages:
-.*:2: Error: file number less than one
+.*:2: Warning: file number less than one, ignored
.*:3: Error: missing string
.*:4: Error: file table slot 1 is already occupied.*
.*:8: Error: unassigned file number 3
@@ -9,7 +9,7 @@
.*:19: Error: bad or irreducible absolute expression
.*:23: Error: isa number less than zero
.*:26: Error: bad or irreducible absolute expression
-.*:26: Error: file number less than one
+.*:26: Warning: file number less than one, ignored
.*:27: Error: bad or irreducible absolute expression
.*:28: Error: unknown .loc sub-directive `frobnitz'
.*:29: Error: unknown .loc sub-directive `frobnitz'
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 --- Comment #11 from Mark Wielaard --- Aha, now I see in libstdc++-v3/src/c++11/Makefile.am: if ENABLE_DUAL_ABI # Rewrite the type info for __ios_failure. 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 -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 $< -o tmp-$@ $(rewrite_ios_failure_typeinfo) tmp-$@ > $@ -rm -f tmp-$@ cxx11-ios_failure.lo: cxx11-ios_failure-lt.s $(LTCXXCOMPILE) -g0 -c $< -o $@ cxx11-ios_failure.o: cxx11-ios_failure.s $(CXXCOMPILE) -g0 -c $< endif Then my workaround of checking for debug_info_level > DINFO_LEVEL_NONE indeed wouldn't work. It is explicitly generating debuginfo for the assembly file and then adding -g0 when turning the assembly file into an object file. So that is too late. I don't think adding -gno-as-loc-support to the -S invocation will work because of the definition of asm_outputs_debug_line_str () which is true if dwarf_version >= 5 && ! output_asm_line_debug_info () && DWARF5_USE_DEBUG_LINE_STR. So then it will still generate the .file 0 directive. Ideally gas wouldn't error on .file 0, but simply ignore it when not generating DWARF5. Maybe the simplest workaround for now would be also adding -g0 to the -S invocations?
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 --- Comment #10 from H.J. Lu --- (In reply to Jakub Jelinek from comment #9) > Bootstrap is fine if one uses older binutils. > The thing is that cxx11-ios_failure* is built by hand first with -g -O2 -S, > then the assembly is modified by a script and then it is assembled, and as > older assemblers would fail miserably on assembling .s file containing > .debug_info etc. with -g (-gdwarf-2 passed to assembler), the assembly is > invoked with -g -O2 -c -g0. > I really think this should be fixed solely on the assembler side, and > if needed, we can add a temporary workaround, I guess compiling > cxx11-ios_failure* with -gno-as-loc-support could fix that. Assembler option: --gdwarf-generate DWARF debugging information. 2 <= <= 5 both accepts and generates DWARF info. This decision is made very early.
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 --- Comment #9 from Jakub Jelinek --- Bootstrap is fine if one uses older binutils. The thing is that cxx11-ios_failure* is built by hand first with -g -O2 -S, then the assembly is modified by a script and then it is assembled, and as older assemblers would fail miserably on assembling .s file containing .debug_info etc. with -g (-gdwarf-2 passed to assembler), the assembly is invoked with -g -O2 -c -g0. I really think this should be fixed solely on the assembler side, and if needed, we can add a temporary workaround, I guess compiling cxx11-ios_failure* with -gno-as-loc-support could fix that.
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708
--- Comment #8 from Mark Wielaard ---
I am not sure where the -g -O2 -g0 comes from. I must have missed this in my
testing.
The issue is the .file 0 directive, which is special to gas (only valid with
-gdwarf-5).
It is generated by dwarf2out_finish ():
/* Output the source line correspondence table. We must do this
even if there is no line information. Otherwise, on an empty
translation unit, we will generate a present, but empty,
.debug_info section. IRIX 6.5 `nm' will then complain when
examining the file. This is done late so that any filenames
used by the debug_info section are marked as 'used'. */
switch_to_section (debug_line_section);
ASM_OUTPUT_LABEL (asm_out_file, debug_line_section_label);
if (! output_asm_line_debug_info ())
output_line_info (false);
else if (asm_outputs_debug_line_str ())
{
/* When gas outputs DWARF5 .debug_line[_str] then we have to
tell it the comp_dir and main file name for the zero entry
line table. */
const char *comp_dir, *filename0;
comp_dir = comp_dir_string ();
if (comp_dir == NULL)
comp_dir = "";
filename0 = get_AT_string (comp_unit_die (), DW_AT_name);
if (filename0 == NULL)
filename0 = "";
fprintf (asm_out_file, "\t.file 0 ");
output_quoted_string (asm_out_file, remap_debug_filename (comp_dir));
fputc (' ', asm_out_file);
output_quoted_string (asm_out_file, remap_debug_filename (filename0));
fputc ('\n', asm_out_file);
}
So it looks like the asm_outputs_debug_line_str () is wrong:
/* Returns TRUE if we are outputting DWARF5 and the assembler supports
DWARF5 .debug_line tables using .debug_line_str or we generate
it ourselves, except for split-dwarf which doesn't have a
.debug_line_str. */
static bool
asm_outputs_debug_line_str (void)
{
if (dwarf_version >= 5
&& ! output_asm_line_debug_info ()
&& DWARF5_USE_DEBUG_LINE_STR)
return true;
else
{
#if defined(HAVE_AS_GDWARF_5_DEBUG_FLAG) &&
defined(HAVE_AS_WORKING_DWARF_N_FLAG)
return !dwarf_split_debug_info && dwarf_version >= 5;
#else
return false;
#endif
}
}
It probably should check debug_info_level > DINFO_LEVEL_NONE.
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 --- Comment #7 from Jakub Jelinek --- I'd be for automatic bumping to dwarf5 level if .file 0 is seen, but remember that it happened and issue an error if .debug_info with version older than 5 is seen in the file.
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 --- Comment #6 from Jakub Jelinek --- The assembler has all the information in the assembly, .debug_info section contains version etc.
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 --- Comment #5 from Jakub Jelinek --- Ah, no, the *.s file is generated with -g, but the assembler isn't able to cope with it. I'd say that the assembler shouldn't require any directive or flag but just assemble it. Anything else seems to be an assembler bug.
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 Jakub Jelinek changed: What|Removed |Added CC||jakub at gcc dot gnu.org --- Comment #4 from Jakub Jelinek --- I guess the primary question is why does it emit any .file directives or .debug_str when it is compiled with -g -O2 -g0. That seems like the bug.
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 H.J. Lu changed: What|Removed |Added Target Milestone|--- |11.0 --- Comment #3 from H.J. Lu --- The assembler patch is posted at https://sourceware.org/pipermail/binutils/2021-January/114978.html GCC should emit ".dwarf_level 5" when generating DWARF5 info.
[Bug debug/98708] [11 Regression] cxx11-ios_failure-lt.s:36733: Error: file number less than one by r11-6755
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98708 H.J. Lu changed: What|Removed |Added Summary|[11 Regression] |[11 Regression] |cxx11-ios_failure-lt.s:3673 |cxx11-ios_failure-lt.s:3673 |3: Error: file number less |3: Error: file number less |than one|than one by r11-6755 --- Comment #2 from H.J. Lu --- /bin/sh ../../libtool --tag CXX --tag disable-shared --mode=compile /export/gnu/import/git/gcc-test-master-intel64-native/bld/./gcc/xgcc -shared-libgcc -B/export/gnu/import/git/gcc-test-master-intel64-native/bld/./gcc -nostdinc++ -L/export/gnu/import/git/gcc-test-master-intel64-native/bld/x86_64-pc-linux-gnu/libstdc++-v3/src -L/export/gnu/import/git/gcc-test-master-intel64-native/bld/x86_64-pc-linux-gnu/libstdc++-v3/src/.libs -L/export/gnu/import/git/gcc-test-master-intel64-native/bld/x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs -B/usr/11.0.0/x86_64-pc-linux-gnu/bin/ -B/usr/11.0.0/x86_64-pc-linux-gnu/lib/ -isystem /usr/11.0.0/x86_64-pc-linux-gnu/include -isystem /usr/11.0.0/x86_64-pc-linux-gnu/sys-include -fno-checking -I/export/gnu/import/git/gcc-test-master-intel64-native/src-master/libstdc++-v3/../libgcc -I/export/gnu/import/git/gcc-test-master-intel64-native/bld/x86_64-pc-linux-gnu/libstdc++-v3/include/x86_64-pc-linux-gnu -I/export/gnu/import/git/gcc-test-master-intel64-native/bld/x86_64-pc-linux-gnu/libstdc++-v3/include -I/export/gnu/import/git/gcc-test-master-intel64-native/src-master/libstdc++-v3/libsupc++ -std=gnu++11 -prefer-pic -D_GLIBCXX_SHARED -fno-implicit-templates -Wall -Wextra -Wwrite-strings -Wcast-qual -Wabi=2 -fdiagnostics-show-location=once -ffunction-sections -fdata-sections -frandom-seed=cxx11-ios_failure.lo -g -O2 -D_GNU_SOURCE -fcf-protection -mshstk -g0 -c cxx11-ios_failure-lt.s -o cxx11-ios_failure.lo cxx11-ios_failure-lt.s contains DWARF5 debug info. Since -g0 is used, --gdwarf-5 isn't passed to assembler: [hjl@gnu-clx-1 gcc]$ ./xgcc -B./ -c /tmp/cxx11-ios_failure-lt.s /tmp/cxx11-ios_failure-lt.s: Assembler messages: /tmp/cxx11-ios_failure-lt.s:36733: Error: file number less than one [hjl@gnu-clx-1 gcc]$ ./xgcc -B./ -c /tmp/cxx11-ios_failure-lt.s -g [hjl@gnu-clx-1 gcc]$ This means that "gcc -c" no longer works on assembly codes generated with -g when DWARF5 is enabled.
