Hi! This testcase fails on the 4.9 branch (where C89 is the default) on 32-bit targets, because of warning: this decimal constant is unsigned only in ISO C90 warning. On the trunk it doesn't warn because we default to C11. In any case, the testcase also fails the same way before the r218205 fix and succeeds with it if I add U suffix, so I've committed this fix to trunk and 4.9 branches as obvious.
2014-12-15 Jakub Jelinek <ja...@redhat.com> PR tree-optimization/63551 * gcc.dg/ipa/pr63551.c (fn2): Use 4294967286U instead of 4294967286 to avoid warnings. --- gcc/testsuite/gcc.dg/ipa/pr63551.c.jj 2014-12-01 14:57:16.000000000 +0100 +++ gcc/testsuite/gcc.dg/ipa/pr63551.c 2014-12-15 11:41:27.866596259 +0100 @@ -21,7 +21,7 @@ void fn2 () { d = 0; - union U b = { 4294967286 }; + union U b = { 4294967286U }; fn1 (b); } Jakub