https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101046
--- Comment #7 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-9 branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:2f682080c136412897b5d350abb337e694ad51de commit r9-10076-g2f682080c136412897b5d350abb337e694ad51de Author: Jakub Jelinek <ja...@redhat.com> Date: Tue Jun 15 11:36:47 2021 +0200 expr: Fix up VEC_PACK_TRUNC_EXPR expansion [PR101046] The following testcase ICEs, because we have a mode mismatch. VEC_PACK_TRUNC_EXPR's operands have different modes from the result (same vector mode size but twice as large element), but we were passing non-NULL subtarget with the mode of the result to the expansion of its arguments, so the VEC_PERM_EXPR in one of the operands which had V8SImode operands and result had V16HImode target. Fixed by clearing the subtarget if we are changing mode. 2021-06-15 Jakub Jelinek <ja...@redhat.com> PR target/101046 * expr.c (expand_expr_real_2) <case VEC_PACK_FIX_TRUNC_EXPR, case VEC_PACK_TRUNC_EXPR>: Clear subtarget when changing mode. (cherry picked from commit 008153c8435ca3bf587e11654c31f05c0f99b43a)