https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69987
Bug ID: 69987 Summary: [6 Regression] internal compiler error: in verify_loop_structure, at cfgloop.c:1639 Product: gcc Version: 6.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end Assignee: unassigned at gcc dot gnu.org Reporter: Joost.VandeVondele at mat dot ethz.ch Target Milestone: --- an overnight regression on trunk, which I'll tr to reduce: /data/vjoost/gnu/cp2k/cp2k/makefiles/../src/cp_lbfgs.F:242:0: SUBROUTINE mainlb(n, m, x, l, u, nbd, f, g, factr, pgtol, ws, wy, & Error: loop verification on loop tree that needs fixup /data/vjoost/gnu/cp2k/cp2k/makefiles/../src/cp_lbfgs.F:242:0: internal compiler error: in verify_loop_structure, at cfgloop.c:1639 0x773ecc verify_loop_structure() ../../gcc/gcc/cfgloop.c:1639 0xd07b50 checking_verify_loop_structure ../../gcc/gcc/cfgloop.h:324 0xd07b50 tree_transform_and_unroll_loop(loop*, unsigned int, edge_def*, tree_niter_desc*, void (*)(loop*, void*), void*) ../../gcc/gcc/tree-ssa-loop-manip.c:1362 0xd19205 loop_prefetch_arrays ../../gcc/gcc/tree-ssa-loop-prefetch.c:1908 0xd19205 tree_ssa_prefetch_arrays() ../../gcc/gcc/tree-ssa-loop-prefetch.c:1977 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <http://gcc.gnu.org/bugs.html> for instructions. make[2]: *** [cp_lbfgs.o] Error 1 First guess would be this is related to the fix of PR69740 (which was also backported to the 5 branch).