[Bug sanitizer/55739] asan doesn't work on common symbols

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55739

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-12-19 13:26:34 UTC ---
That is not a bug, it can't.  Asan needs to insert padding after it, but you
don't know if the symbol will be defined by the current CU, or some other, and
whether there will be padding inserted after it or not.  Just use -fno-common
if the program doesn't assume common symbol behavior to instrument those.