http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54489
--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-09-05 13:52:25 UTC --- Testcase: int foo (int a) { int b = 0; #define X if (a) b = b + 1; #define XX X X X X X X X X X X #define XXX XX XX XX XX XX XX XX XX XX XX #define XXXX XXX XXX XXX XXX XXX XXX XXX XXX XXX XXX #define XXXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX XXXX #define XXXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX XXXXX #define XXXXXXX XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX XXXXXX return b; } also relevant is the testcase from PR54492 which we should not regress.