No redzones for weak symbols

[GoogleCodeExporter]

ASan does not catch global buffer overflow in the following example:

#include <stdio.h>

__attribute__((weak)) char zz[10] = "012345678";

int main(void) {
        for (int i = 0; i < 11; ++i) {
                zz[i] = '5';
        }
        printf("%s\n", zz);
        return 0;
}

Original issue reported on code.google.com by euge...@google.com on 7 Oct 2011 at 7:22