No, const doesn't make any difference. On looking again at the source, I've come to the conclusion that this isn't a vectorizer bug after all. It is simply a coding error.
A compiler is allowed to assume that a pointer to a type is aligned suitably for the type. So in *(apr_uint32_t *)target = *(apr_uint32_t *)source; gcc is allowed to assume that source and target are 4-byte aligned, but they are not.. Modifying the code to use an unaligned 4-byte type here cures the problem. Quoting from ISO/IEC 9899:1999 6.3.2.3 Pointers ... 7 A pointer to an object or incomplete type may be converted to a pointer to a different object or incomplete type. If the resulting pointer is not correctly aligned for the pointed-to type, the behavior is undefined. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1353142 Title: subversion tests fail on ppc64el when built with -O3 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gcc-4.9/+bug/1353142/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
