http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55679
--- Comment #15 from Jack Howarth <howarth at nitro dot med.uc.edu> 2012-12-15 03:09:31 UTC --- The absence of RLIMIT_AS support on darwin appears to be a longstanding issue... http://lists.apple.com/archives/Unix-porting/2007/Apr/msg00026.html and really should be fixed since SUSv3 Unix (which darwin claims to be) demands it.
