[Bug libstdc++/12873] New: __cxa_demangle not working as specified in ABI

["rmerkert at alphatech dot com" <gcc-bugzilla at gcc dot gnu dot org>]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12873

           Summary: __cxa_demangle not working as specified in ABI
           Product: gcc
           Version: 3.3.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: libstdc++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: rmerkert at alphatech dot com
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: gcc (GCC) 3.4 20031026 (experimental)

This test program produces different results for 3.3.2 and 3.4.

cat > test.c <<EOF
#include <stdio.h>
#include <stdlib.h>

extern char *__cxa_demangle (const char *__mangled_name,
                             char *__output_buffer,
                             __SIZE_TYPE__ *__length,
                             int *__status);


int main(int argc, char** argv)
{
  for (int i=1;i<argc;++i) {
    int status;
    char* res = __cxa_demangle(argv[i],0,0,&status);
    if (res!=NULL || status!=0) {
      printf("Demangled '%s' as '%s'\n",argv[i],res);
    }
    else {
      printf("Could not demangle '%s'\n",argv[i]);
    }
    free(res);
  }
  return 0;
}

EOF

/local/gcc/bin/gcc -o test test.c -std=c99 /local/gcc/lib/libstdc++.a

'./test hello'

produces

Demangled 'hello' as 'unsigned char'

Also, if I don't pass the status flag pointer, then  I get 

Could not demangle 'hello'


Code is working in mainline, but it would be nice to have it work in 3.3
release series as well. 

Can this be backported?