https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80136
--- Comment #12 from Christophe Lyon <clyon at gcc dot gnu.org> --- Following Jakub's recommendation, I applied this: diff --git a/gcc/tree-stdarg.c b/gcc/tree-stdarg.c index 18dd972..edf47d1 100644 --- a/gcc/tree-stdarg.c +++ b/gcc/tree-stdarg.c @@ -1061,8 +1061,7 @@ expand_ifn_va_arg_1 (function *fun) else { gimple_seq tmp_seq; - force_gimple_operand (expr, &tmp_seq, false, NULL_TREE); - gimple_seq_add_seq_without_update (&pre, tmp_seq); + gimplify_and_add (expr, &pre); } input_location = saved_location; on top of r246319 (that is, before you reverted it). and my build now completes. I didn't run make-check though.