https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86850
--- Comment #3 from rguenther at suse dot de <rguenther at suse dot de> --- On Tue, 21 Aug 2018, dcb314 at hotmail dot com wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86850 > > --- Comment #2 from David Binderman <dcb314 at hotmail dot com> --- > Indeed it does look like vectorizer code. Here are 20 frames, > found by using the UBSAN_OPTIONS=print_stacktrace=1 option: OK, I suppose we're creating a SLP node for a PHI where there are zero operands and thus no children and SLP_TREE_CHILDREN (node).create (nops); will not create a vector but a splice of an empty vector will barf when splicing into it. Index: gcc/tree-vect-slp.c =================================================================== --- gcc/tree-vect-slp.c (revision 263656) +++ gcc/tree-vect-slp.c (working copy) @@ -1489,7 +1489,9 @@ fail: node = vect_create_new_slp_node (stmts); SLP_TREE_TWO_OPERATORS (node) = two_operators; - SLP_TREE_CHILDREN (node).splice (children); + gcc_assert (children.length () == nops); + if (!children.is_empty ()) + SLP_TREE_CHILDREN (node).splice (children); return node; }
