[Bug c/48666] New: [4.5.2/4.6 regression] -Warray-bounds doesn't trigger anymore for simple case

[franz.sirl-kernel at lauterbach dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48666

           Summary: [4.5.2/4.6 regression] -Warray-bounds doesn't trigger
                    anymore for simple case
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: franz.sirl-ker...@lauterbach.com


Created attachment 24031
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=24031
testcase

A simple testcase like

typedef union
{
          int val32;
          int val32Tab2[4];
          int val32Tab3[3];
          long long val64;
} SrcVal;

void f(SrcVal *x)
{
  x->val32Tab3[4] = 42;
}

doesn't warn anymore when compiled with -O2 -Warray-bounds.

Tested OK (x86_64):
gcc-4.3 (SLES11): gcc (SUSE Linux) 4.3.4 [gcc-4_3-branch revision 152973]
gcc-4.5.1 (FC14): gcc (GCC) 4.5.1 20100924 (Red Hat 4.5.1-4)

Tested NOT OK (x86_64):
gcc-4.5.2 (OBS): gcc-4.5 (SUSE Linux) 4.5.2 20110302 [gcc-4_5-branch revision
170616]
gcc-4.6.0 (OBS): gcc-4.6 (SUSE Linux) 4.6.0 20110314 [gcc-4_6-branch revision
170941]
gcc-4.6.0 (OBS): gcc-4.6 (SUSE Linux) 4.6.0 20110415 [gcc-4_6-branch revision
172496]