This testcase will cause an internel error when compiled with options "-O3 -fprefetch-loop-arrays" on IA-64 + Linux.
SUBROUTINE EBJFT() dimension nmw(140) if(k.eq.0) goto 10 go to 30 10 continue do 20 l=1, 140 20 nmw(l)= 0.0D0 30 continue go to (10)lsn do 40 j=1, 140 nmwj=nmw(j) 40 continue write(*,*) nmwj end The error message is: prefetch-err.f: In function âebjftâ? prefetch-err.f:3: error: edge from 50 to 36 should be marked irreducible prefetch-err.f:3: internal compiler error: in verify_loop_structure, at cfgloop.c:1268 Please submit a full bug report, with preprocessed source if appropriate. See <URL:http://gcc.gnu.org/bugs.html> for instructions. -- Summary: Internal compiler error in verify_loop_structure Product: gcc Version: 4.2.0 Status: UNCONFIRMED Severity: minor Priority: P3 Component: tree-optimization AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: canqun at nudt dot edu dot cn GCC build triplet: ia64-unkown-linux GCC host triplet: ia64-unkown-linux GCC target triplet: ia64-unkown-linux http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27872