The testcase int f[__builtin_constant_p(&"Hello"[0])?1:-1];
did work on gcc 3.4, but doesn't any longer on 4.0 and 4.1. The parser gets an integer constant node from fold_builtin, but still thinks it is not a compile time constant for the array bound. -- Summary: [4.0/4.1 regression] __builtin_constant_p(&"Hello"[0])?1:-1 not compile-time constant Product: gcc Version: 4.1.0 Status: UNCONFIRMED Keywords: rejects-valid, missed-optimization Severity: normal Priority: P2 Component: c++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: rguenth at gcc dot gnu dot org CC: gcc-bugs at gcc dot gnu dot org BugsThisDependsOn: 21595 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21619