http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20262
Geoff Romer <gromer at google dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |gromer at google dot com --- Comment #5 from Geoff Romer <gromer at google dot com> --- The issue isn't the flexibility in "presumed", it's the flexibility in "source line": the standard defines line number in terms of the "current token", but gives no explicit guidance about which token is considered "current" in a case like this, where the preprocessor is arguably expanding two different macros at the same time.