From 7dfffe32419a963660f5c04b40b8f0becd509b69 Mon Sep 17 00:00:00 2001 From: Nathan Sidwell Date: Tue, 22 Sep 2020 09:00:20 -0700 Subject: [PATCH] c++: fix injected friend of template class In working on fixing hiddenness, I discovered some suspicious code in template instantiation. I suspect it dates from when we didn't do the hidden friend injection thing at all. The xreftag finds the same class, but makes it visible to name lookup. Which is wrong. hurrah, fixing a bug by deleting code! gcc/cp/ * pt.c (instantiate_class_template_1): Do not repush and unhide injected friend. gcc/testsuite/ * g++.old-deja/g++.pt/friend34.C: Check injected friend is still invisible. --- gcc/cp/pt.c | 19 ------------------- gcc/testsuite/g++.old-deja/g++.pt/friend34.C | 5 ++++- 2 files changed, 4 insertions(+), 20 deletions(-) diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c index 97d0c245f7e..44ca14afc4e 100644 --- a/gcc/cp/pt.c +++ b/gcc/cp/pt.c @@ -12030,25 +12030,6 @@ instantiate_class_template_1 (tree type) adjust_processing_template_decl = true; --processing_template_decl; } - else if (TREE_CODE (friend_type) != BOUND_TEMPLATE_TEMPLATE_PARM - && !CLASSTYPE_USE_TEMPLATE (friend_type) - && TYPE_HIDDEN_P (friend_type)) - { - /* friend class C; - - where C hasn't been declared yet. Let's lookup name - from namespace scope directly, bypassing any name that - come from dependent base class. */ - tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type)); - - /* The call to xref_tag_from_type does injection for friend - classes. */ - push_nested_namespace (ns); - friend_type = - xref_tag_from_type (friend_type, NULL_TREE, - /*tag_scope=*/ts_current); - pop_nested_namespace (ns); - } else if (uses_template_parms (friend_type)) /* friend class C; */ friend_type = tsubst (friend_type, args, diff --git a/gcc/testsuite/g++.old-deja/g++.pt/friend34.C b/gcc/testsuite/g++.old-deja/g++.pt/friend34.C index 5e80ab98b2e..dcd6df0ce55 100644 --- a/gcc/testsuite/g++.old-deja/g++.pt/friend34.C +++ b/gcc/testsuite/g++.old-deja/g++.pt/friend34.C @@ -6,9 +6,12 @@ template class bar { public: - friend class foo; // this is not bar::foo, it forward-declares ::foo + friend class foo; // this is not bar::foo, it injects hidden ::foo class foo {}; bar() { foo(); } // but this should refer to bar::foo }; bar<> baz; + +// We still have not made foo visible. +foo *b; // { dg-error "does not name a type" } -- 2.30.2