Since at least revision 130630 (but not in 130463), the gfortran testsuite has a lot of failures with -O3 on powerpc-apple-darwin9 not present on i686-apple-darwin9 nor powerpc-apple-darwin8. A reduced case is:
[karma] f90/bug% cat scalarize_ref.f90 ! Program to test the scalarizer program testarray implicit none integer, dimension (6, 5) :: a a = 0 a(1,2) = 2 ! The following expression should cause loop reordering a(:, 2:4) = a(:, 1:3) if (a(1, 3) .ne. 2) call abort end program [karma] f90/bug% gfc -O3 scalarize_ref.f90 scalarize_ref.f90: In function 'testarray': scalarize_ref.f90:2: internal compiler error: tree check: expected ssa_name, have symbol_memory_tag in is_old_name, at tree-into-ssa.c:566 Please submit a full bug report, with preprocessed source if appropriate. See <http://gcc.gnu.org/bugs.html> for instructions. As far as I can tell, it requires both a(:, 2:4) = a(:, 1:3) and if (a(1, 3) .ne. 2) call abort -- Summary: internal compiler error: tree check: expected ssa_name, have symbol_memory_tag in is_old_name, at tree-into- ssa.c:566 Product: gcc Version: 4.3.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: dominiq at lps dot ens dot fr GCC build triplet: powerpc-apple-darwin9 GCC host triplet: powerpc-apple-darwin9 GCC target triplet: powerpc-apple-darwin9 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34375