From 718c32a39895ea12ff79f05d6001d7401e6e7e11 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Tue, 30 Mar 2021 18:15:32 +0200 Subject: c++: Fix ICE on PTRMEM_CST in lambda in inline var initializer [PR99790] The following testcase ICEs (since the addition of inline var support), because the lambda contains PTRMEM_CST but finish_function is called for the lambda quite early during parsing it (from finish_lambda_function) when the containing class is still incomplete. That means that during genericization cplus_expand_constant keeps the PTRMEM_CST unmodified, but later nothing lowers it when the class is finalized. Using sizeof etc. on the class in such contexts is rejected by both g++ and clang++, and when the PTRMEM_CST appears e.g. in static var initializers rather than in functions, we handle it correctly because c_parse_final_cleanups -> lower_var_init will handle those cplus_expand_constant when all classes are already finalized. The following patch fixes it by calling cplus_expand_constant again during gimplification, as we are now unconditionally unit at a time, I'd think everything that could be completed will be before we start gimplification. 2021-03-30 Jakub Jelinek PR c++/99790 * cp-gimplify.c (cp_gimplify_expr): Handle PTRMEM_CST. * g++.dg/cpp1z/pr99790.C: New test. (cherry picked from commit 7cdd30b43a63832d6f908b2dd64bd19a0817cd7b) --- gcc/cp/cp-gimplify.c | 8 ++++++++ gcc/testsuite/g++.dg/cpp1z/pr99790.C | 9 +++++++++ 2 files changed, 17 insertions(+) create mode 100644 gcc/testsuite/g++.dg/cpp1z/pr99790.C (limited to 'gcc') diff --git a/gcc/cp/cp-gimplify.c b/gcc/cp/cp-gimplify.c index 113a46a..1bf887f 100644 --- a/gcc/cp/cp-gimplify.c +++ b/gcc/cp/cp-gimplify.c @@ -839,6 +839,14 @@ cp_gimplify_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p) } break; + case PTRMEM_CST: + *expr_p = cplus_expand_constant (*expr_p); + if (TREE_CODE (*expr_p) == PTRMEM_CST) + ret = GS_ERROR; + else + ret = GS_OK; + break; + case RETURN_EXPR: if (TREE_OPERAND (*expr_p, 0) && (TREE_CODE (TREE_OPERAND (*expr_p, 0)) == INIT_EXPR diff --git a/gcc/testsuite/g++.dg/cpp1z/pr99790.C b/gcc/testsuite/g++.dg/cpp1z/pr99790.C new file mode 100644 index 0000000..99961f5 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp1z/pr99790.C @@ -0,0 +1,9 @@ +// PR c++/99790 +// { dg-do compile { target c++17 } } + +struct A; +struct B { void (*fn) (A *); }; +template +int foo (const T &); +struct A { int a; static constexpr B b{[] (A *n) { n->*&A::a = 2; }}; }; +int a = foo (A::b); -- cgit v1.1