Please read http://gcc.gnu.org/bugs.html, you should provide a self-contained and if possible small testcase, it could very well be a bug in the application you are using. If you suspect a gcc bug, you can use use either a debugger or brute-force - e.g. binary search in between objects compiled with various compilation flags or various versions of the compiler (-O0 vs. standard flags, or standard flags + -fno-strict-aliasing, etc.).
Please read http:// gcc.gnu. org/bugs. html, you should provide a self-contained and if possible small testcase, it could very well be a bug in the application you are using. If you suspect a gcc bug, you can use use either a debugger or brute-force - e.g. binary search in between objects compiled with various compilation flags or various versions of the compiler (-O0 vs. standard flags, or standard flags + -fno-strict- aliasing, etc.).