Hi! The r11-7528 build_co_await changes broke coroutines on arm*-linux-gnuabi, 2780 ^FAIL.*coroutines/ in total. The problem is that arm is targetm.cxx.cdtor_return_this target where both ctors and dtors in the ABI return this pointer rather than void, and build_new_method_call_1 does: else if (call != error_mark_node && DECL_DESTRUCTOR_P (cand->fn) && !VOID_TYPE_P (TREE_TYPE (call))) /* An explicit call of the form "x->~X()" has type "void". However, on platforms where destructors return "this" (i.e., those where targetm.cxx.cdtor_returns_this is true), such calls will appear to have a return value of pointer type to the low-level call machinery. We do not want to change the low-level machinery, since we want to be able to optimize "delete f()" on such platforms as "operator delete(~X(f()))" (rather than generating "t = f(), ~X(t), operator delete (t)"). */ call = build_nop (void_type_node, call); The new code in build_co_await relies on build_special_member_call returned expression being a CALL_EXPR, but due to the build_nop in there it is a NOP_EXPR around the CALL_EXPR. It can't be stripped with STRIP_NOPS because void has different mode from the pointer mode.
Bootstrapped/regtested on armv7hl-linux-gnueabi and x86_64-linux, ok for trunk? 2021-03-09 Jakub Jelinek <ja...@redhat.com> PR c++/99459 * coroutines.cc (build_co_await): Look through NOP_EXPRs in build_special_member_call return value to find the CALL_EXPR. --- gcc/cp/coroutines.cc.jj 2021-03-05 21:51:48.671185716 +0100 +++ gcc/cp/coroutines.cc 2021-03-08 10:53:13.187959339 +0100 @@ -868,6 +868,8 @@ build_co_await (location_t loc, tree a, = build_special_member_call (a, complete_dtor_identifier, NULL, a_type, LOOKUP_NORMAL, tf_none); + if (dummy && CONVERT_EXPR_P (dummy)) + dummy = TREE_OPERAND (dummy, 0); dummy = dummy ? TREE_OPERAND (CALL_EXPR_FN (dummy), 0) : NULL_TREE; if (dummy && coro_diagnose_throwing_fn (dummy)) @@ -1031,6 +1033,8 @@ build_co_await (location_t loc, tree a, = build_special_member_call (e_proxy, complete_dtor_identifier, NULL, o_type, LOOKUP_NORMAL, tf_none); + if (dummy && CONVERT_EXPR_P (dummy)) + dummy = TREE_OPERAND (dummy, 0); dummy = dummy ? TREE_OPERAND (CALL_EXPR_FN (dummy), 0) : NULL_TREE; if (dummy && coro_diagnose_throwing_fn (dummy)) Jakub