This is with the Polyhedron aermod.f90 test case (http://www.polyhedron.co.uk/pb05/polyhedron_benchmark_suite.html).
The program crashes (in << 1 sec) with gfortran -funroll-loops -march=opteron -O2 -g aermod.f90 It does not crash: - without: -march=opteron - without: -funroll-loops - with: -O1 It was working on 2007-04-23 (should be r124055) and started to fail since 2007-04-24 (should be r124093). gdb shows: Program received signal SIGSEGV, Segmentation fault. #0 resini_ () at aermod.f90:23766 #1 0x00000000004c7357 in MAIN__ () at aermod.f90:2189 And valgrind: ==6590== Invalid write of size 4 ==6590== at 0x4066D1: resini_ (aermod.f90:23766) ==6590== by 0x4C8BD6: MAIN__ (aermod.f90:2189) ==6590== by 0x4C95AB: main (fmain.c:22) ==6590== Address 0x1BE65FD0 is not stack'd, malloc'd or (recently) free'd 23757 DO K = 1 , NUMGRP 23758 DO J = 1 , NUMREC 23759 AVEVAL(J,K,L,M) = 0.0 23760 DO I = 1 , NHIVAL 23761 HIVALU(J,I,K,L,M) = 0.0 23762 NHIDAT(J,I,K,L,M) = 0 23763 HCLMSG(J,I,K,L,M) = ' ' 23764 HMAX(I,K,L,M) = 0.0 23765 HMDATE(I,K,L,M) = 0 23766 HMLOC(I,K,L,M) = 0 23767 HMCLM(I,K,L,M) = ' ' 23768 ENDDO 23769 ENDDO -- Summary: [Regression 4.3] Crash of gen. prog. when using - funroll-loops -march=opteron Product: gcc Version: 4.3.0 Status: UNCONFIRMED Keywords: wrong-code Severity: normal Priority: P3 Component: middle-end AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: burnus at gcc dot gnu dot org GCC target triplet: x86_64-unknown-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31697