http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49540
Summary: [4.6/4.7 Regression] Memory-hot with large DATA stmt Product: gcc Version: 4.6.1 Status: UNCONFIRMED Keywords: memory-hog Severity: normal Priority: P3 Component: fortran AssignedTo: unassig...@gcc.gnu.org ReportedBy: ja...@gcc.gnu.org COMMON/A/B(100000,100) DATA B/10000000*0.0/ END used to compile in just a couple of MB of memory and fraction of a second, but starting with http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=159076 it needs over 5GB of RAM and very long time. That is only small fragment from original real-world testcase, which contains: PARAMETER (MAXSTR=150001) c... COMMON/HJJET2/NSG,NJSG(MAXSTR),IASG(MAXSTR,3),K1SG(MAXSTR,100), & K2SG(MAXSTR,100),PXSG(MAXSTR,100),PYSG(MAXSTR,100), & PZSG(MAXSTR,100),PESG(MAXSTR,100),PMSG(MAXSTR,100) c... DATA NSG/0/,NJSG/150001*0/,IASG/450003*0/, & K1SG/15000100*0/,K2SG/15000100*0/, & PXSG/15000100*0.0/,PYSG/15000100*0.0/,PZSG/15000100*0.0/, & PESG/15000100*0.0/,PMSG/15000100*0.0/ c... END c... which compiled just fine with gcc up to 4.5.x and with 4.6/4.7 it is basically out of any hope to compile it.