[Bug tree-optimization/18828] New: [4.0 Regression] Extraneous warning with var_start and optimization

[pinskia at gcc dot gnu dot org]

typedef __builtin_va_list __gnuc_va_list;
typedef __gnuc_va_list va_list;

extern void abort (void);

void foo (int size, ...)
{
  va_list ap;
  if (size != 21)
    abort ();
  __builtin_va_start(ap,size);
  __builtin_va_end(ap);
}

I found this while fixing another bug.

-- 
           Summary: [4.0 Regression] Extraneous warning with var_start and
                    optimization
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Keywords: diagnostic
          Severity: normal
          Priority: P2
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pinskia at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18828