[Bug bootstrap/37441] New: [4.4 regression] dwarf2 unwind info patches produce undefined symbols

["ro at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

Between 20080801 and 20080903, mainline bootstrap started to fail on IRIX 6.5.
The symptom is a configuration failure when configuring stage2 support
libraries
like zlib:

checking whether the 
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/xgcc
-B/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/
-B/vol/gcc/mips-sgi-irix6.5/bin/ linker (/usr/bin/ld -n32) supports shared
libraries... configure: error: Link tests are not allowed after
GCC_NO_EXECUTABLES.
make[2]: *** [configure-stage2-zlib]

>From zlib/config.log, it seems like the checking for suffix of executables test
fails:

configure:2484:  /vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/xgcc
-B/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/
-B/vol/gcc/mips-sgi-irix6.5/bin/ -o conftest -g -O2   conftest.c  >&5
ld32: ERROR   33 : Unresolved data symbol ".LSFDE0" -- 1st referenced by
/var/tmp//ccrBXRSg.o.
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE2" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE4" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE6" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE8" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE10" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE12" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE14" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE16" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE18" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE20" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE22" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE24" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE26" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE28" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE30" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE32" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE34" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE36" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE38" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE40" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE42" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: ERROR   33 : Unresolved data symbol ".LSFDE44" -- 1st referenced by
/vol/gccsrc/obj/gcc-4.4.0-20080903/6.5-gcc/./prev-gcc/libgcc_eh.a(unwind-dw2-fde.o).
        Use linker option -v to see when and which objects, archives and dsos
are loaded.  
ld32: INFO    152: Output file removed because of error.
collect2: ld returned 2 exit status
configure:2487: $? = 1

With the following conftest.c

int
main ()
{

  ;
  return 0;
}

gcc -g -O2   conftest.c -v -save-temps -dA -fverbose-asm

works successfully as of 20080801, while the 20080903 version fails to link as
above.  It turns out that both .s files contain a reference to the .LSFDE0
label (from DW_AT_MIPS_fde), but the definition is lost.  I've included both .s
files
for reference.  With -fno-dwarf2-cfi-asm, the problem is gone in conftest.s,
but of course the undefined .LSFDE* symbols in libgcc_eh.a remain.


-- 
           Summary: [4.4 regression] dwarf2 unwind info patches produce
                    undefined symbols
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: ro at gcc dot gnu dot org
 GCC build triplet: mips-sgi-irix6.5
  GCC host triplet: mips-sgi-irix6.5
GCC target triplet: mips-sgi-irix6.5


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37441