http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59229
--- Comment #4 from Dominique d'Humieres <dominiq at lps dot ens.fr> --- Reduced test case: SUBROUTINE PYGIVE(CHIN) IMPLICIT INTEGER(I-N) CHARACTER CHIN*(*),CHBIT*104,CHNAM*6 LNAM=1 150 LNAM=LNAM+1 IF(CHBIT(LNAM:LNAM).NE.'('.AND.CHBIT(LNAM:LNAM).NE.'='.AND. &LNAM.LE.6) GOTO 150 CHNAM=CHBIT(1:LNAM-1)//' ' RETURN END -O2 is enough to trigger the ICE. Revision 203859 (2013-10-19) is OK, revision 204945(2013-11-18) gives the ICE.