[Bug c/39565] New: Static variable leaves undefined symbol in object file

["edmar at freescale dot com" <gcc-bugzilla at gcc dot gnu dot org>]

Compiling the test case, produces undefined symbols codestrs_4 and codestrs_8,
which will result in a link error.

If the static is dropped or one of the cases in the switch statement is
removed, the object file does not have undefined symbols.


Test case:

static const union codestrs_t_4 {
  struct {
    char str_2[sizeof ("Illegal opcode")];
  };
  char str[0];
} codestrs_4 = { {"Illegal opcode"} };

static const union codestrs_t_8 {
  struct {
    char str_12[sizeof ("Integer divide by zero")];
  };
  char str[0];
} codestrs_8 = { {"Integer divide by zero"} };

const char *
psiginfo (int pinfo)
{
  const char *base = ((void *)0);

  switch (pinfo)
    {
    case 4: base = codestrs_4.str; break;
    case 8: base = codestrs_8.str; break;
    }
  return base;
 }


Compiled with:
gcc -O2 -c
objdump -t 


Result:
cases.o:     file format elf32-powerpc

SYMBOL TABLE:
00000000 l    df *ABS*  00000000 cases.c
00000000 l    d  .text  00000000 .text
00000000 l    d  .data  00000000 .data
00000000 l    d  .bss   00000000 .bss
00000000 l     O .data  00000014 CSWTCH.1
00000000 l    d  .note.GNU-stack        00000000 .note.GNU-stack
00000000 l    d  .comment       00000000 .comment
00000000 l    d  .gnu.attributes        00000000 .gnu.attributes
00000000 g     F .text  00000024 psiginfo
00000000         *UND*  00000000 codestrs_4
00000000         *UND*  00000000 codestrs_8


-- 
           Summary: Static variable leaves undefined symbol in object file
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: edmar at freescale dot com
 GCC build triplet: powerpc-unknown-linux-gnu
  GCC host triplet: powerpc-unknown-linux-gnu
GCC target triplet: powerpc-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39565