From 4e252e23d34932f13f39cc6544bf5c9379fa2a87 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Tue, 9 Mar 2021 16:44:27 +0100 Subject: [PATCH] c++: Fix coroutines on targetm.cxx.cdtor_return_this targets [PR99459] 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. 2021-03-09 Jakub Jelinek PR c++/99459 * coroutines.cc (build_co_await): Look through NOP_EXPRs in build_special_member_call return value to find the CALL_EXPR. Simplify. --- gcc/cp/coroutines.cc | 34 ++++++++++++++++++---------------- 1 file changed, 18 insertions(+), 16 deletions(-) diff --git a/gcc/cp/coroutines.cc b/gcc/cp/coroutines.cc index 897c1a016dd..c5aeb660ae8 100644 --- a/gcc/cp/coroutines.cc +++ b/gcc/cp/coroutines.cc @@ -863,16 +863,17 @@ build_co_await (location_t loc, tree a, suspend_point_kind suspend_kind) final awaiter, so check for a non-throwing DTOR where needed. */ tree a_type = TREE_TYPE (a); if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (a_type)) - { - tree dummy + if (tree dummy = build_special_member_call (a, complete_dtor_identifier, NULL, a_type, LOOKUP_NORMAL, - tf_none); - dummy = dummy ? TREE_OPERAND (CALL_EXPR_FN (dummy), 0) - : NULL_TREE; - if (dummy && coro_diagnose_throwing_fn (dummy)) - return error_mark_node; - } + tf_none)) + { + if (CONVERT_EXPR_P (dummy)) + dummy = TREE_OPERAND (dummy, 0); + dummy = TREE_OPERAND (CALL_EXPR_FN (dummy), 0); + if (coro_diagnose_throwing_fn (dummy)) + return error_mark_node; + } } } else @@ -1026,16 +1027,17 @@ build_co_await (location_t loc, tree a, suspend_point_kind suspend_kind) if (coro_diagnose_throwing_fn (awrs_func)) return error_mark_node; if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (o_type)) - { - tree dummy + if (tree dummy = build_special_member_call (e_proxy, complete_dtor_identifier, NULL, o_type, LOOKUP_NORMAL, - tf_none); - dummy = dummy ? TREE_OPERAND (CALL_EXPR_FN (dummy), 0) - : NULL_TREE; - if (dummy && coro_diagnose_throwing_fn (dummy)) - return error_mark_node; - } + tf_none)) + { + if (CONVERT_EXPR_P (dummy)) + dummy = TREE_OPERAND (dummy, 0); + dummy = TREE_OPERAND (CALL_EXPR_FN (dummy), 0); + if (coro_diagnose_throwing_fn (dummy)) + return error_mark_node; + } } /* We now have three call expressions, in terms of the promise, handle and