[Bug debug/49887] New: [4.7 regression] .debug_macro breaks many Solaris/SPARC tests

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

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49887

           Summary: [4.7 regression] .debug_macro breaks many
                    Solaris/SPARC tests
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: debug
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: ro@gcc.gnu.org
                CC: jakub@gcc.gnu.org
              Host: sparc-sun-solaris2.11
            Target: sparc-sun-solaris2.11
             Build: sparc-sun-solaris2.11


A recent Solaris 11/SPARC bootstrap with Sun as showed many testsuite
regressions:
a considerable number of them were gcc.dg/debug and g++.dg/debug tests at 
-gdwarf-2 -g3, but only with Sun as:

FAIL: gcc.dg/debug/20020220-1.c -gdwarf-2 -g3 (test for excess errors)
Excess errors:
Undefined            first referenced
 symbol                  in file
wm4.0.a88b226d1d8abb1951fbf09c0af98055 /var/tmp//ccV4aG6a.o

The failure vanishes with -save-temps, so I had to provide an unlink.so
that just returns success to capture the output files.  It turns out that
in a regular compile, I've got this section in 20020220-1.s:

    .section    ".debug_macro"
.LLdebug_macro0:
    .uahalf    0x4
    .byte    0x2
    .uaword    .LLdebug_line0
    .byte    0x7
    .uaword    .LLdebug_macro1
    .byte    0x3
    .byte    0
    .byte    0x1
    .byte    0x4
    .byte    0
    .section    ".debug_macro%wm4.0.a88b226d1d8abb1951fbf09c0af98055"
    .group   
wm4.0.a88b226d1d8abb1951fbf09c0af98055,".debug_macro%wm4.0.a88b226d1d8abb1951fbf09c0af98055",#comdat
.LLdebug_macro1:

but the group signature symbol isn't emitted, which leads to the undefined
symbol:

> elfdump -g 20020220-1.broken.o

Group Section:  .group%wm4.0.a88b226d1d8abb1951fbf09c0af98055
     index    flags / section         signature symbol
       [0]   [ COMDAT ]               wm4.0.a88b226d1d8abb1951fbf09c0af98055
       [1]   .debug_macro%wm4.0.a88b226d1d8abb1951fbf09c0af98055 [10]
$ nm 20020220-1.o


20020220-1.broken.o:

[Index]   Value      Size      Type  Bind  Other Shndx   Name

[4]     |         0|         0|SECT |LOCL |0    |6      |
[7]     |         0|         0|SECT |LOCL |0    |2      |
[8]     |         0|         0|SECT |LOCL |0    |4      |
[10]    |         0|         0|SECT |LOCL |0    |12     |
[11]    |         0|         0|SECT |LOCL |0    |7      |
[12]    |         0|         0|SECT |LOCL |0    |3      |
[2]     |         0|         0|SECT |LOCL |0    |10     |
[3]     |         0|         0|SECT |LOCL |0    |9      |
[9]     |         0|         0|SECT |LOCL |0    |11     |
[5]     |         0|         0|SECT |LOCL |0    |5      |
[6]     |         0|         0|SECT |LOCL |0    |8      |
[1]     |         0|         0|FILE |LOCL |0    |ABS    |20020220-1.c
[13]    |        16|       400|FUNC |GLOB |0    |2      |bar
[14]    |         0|        16|FUNC |GLOB |0    |2      |foo
[15]    |       416|        20|FUNC |GLOB |0    |2      |main
[16]    |         0|         0|NOTY |GLOB |0    |UNDEF 
|wm4.0.a88b226d1d8abb1951fbf09c0af98055

I still need to find out why this only happens on SPARC, but on x86 even with
Sun as all is fine.

  Rainer