From 3dd0d3ee1d2a988e7f3a3e8f009fcf328f16d2ed Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Thu, 7 Jan 2021 17:47:18 +0100 Subject: [PATCH] c++, abi: Fix abi_tag attribute handling [PR98481] In GCC10 cp_walk_subtrees has been changed to walk template arguments. As the following testcase, that changed the mangling of some functions. I believe the previous behavior that find_abi_tags_r doesn't recurse into template args has been the correct one, but setting *walk_subtrees = 0 for the types and handling the types subtree walking manually in find_abi_tags_r looks too hard, there are a lot of subtrees and details what should and shouldn't be walked, both in tree.c (walk_type_fields there, which is static) and in cp_walk_subtrees itself. The following patch abuses the fact that *walk_subtrees is an int to tell cp_walk_subtrees it shouldn't walk the template args. Co-authored-by: Jason Merrill gcc/cp/ChangeLog: PR c++/98481 * class.c (find_abi_tags_r): Set *walk_subtrees to 2 instead of 1 for types. (mark_abi_tags_r): Likewise. * decl2.c (min_vis_r): Likewise. * tree.c (cp_walk_subtrees): If *walk_subtrees_p is 2, look through typedefs. gcc/testsuite/ChangeLog: PR c++/98481 * g++.dg/abi/abi-tag24.C: New test. --- gcc/cp/class.c | 8 ++++++++ gcc/cp/decl2.c | 7 ++++--- gcc/cp/tree.c | 22 ++++++++++++++++------ gcc/testsuite/g++.dg/abi/abi-tag24.C | 17 +++++++++++++++++ 4 files changed, 45 insertions(+), 9 deletions(-) create mode 100644 gcc/testsuite/g++.dg/abi/abi-tag24.C diff --git a/gcc/cp/class.c b/gcc/cp/class.c index c41ac7d..00c0dba 100644 --- a/gcc/cp/class.c +++ b/gcc/cp/class.c @@ -1507,6 +1507,10 @@ mark_or_check_tags (tree t, tree *tp, abi_tag_data *p, bool val) static tree find_abi_tags_r (tree *tp, int *walk_subtrees, void *data) { + if (TYPE_P (*tp) && *walk_subtrees == 1) + /* Tell cp_walk_subtrees to look though typedefs. */ + *walk_subtrees = 2; + if (!OVERLOAD_TYPE_P (*tp)) return NULL_TREE; @@ -1527,6 +1531,10 @@ find_abi_tags_r (tree *tp, int *walk_subtrees, void *data) static tree mark_abi_tags_r (tree *tp, int *walk_subtrees, void *data) { + if (TYPE_P (*tp) && *walk_subtrees == 1) + /* Tell cp_walk_subtrees to look though typedefs. */ + *walk_subtrees = 2; + if (!OVERLOAD_TYPE_P (*tp)) return NULL_TREE; diff --git a/gcc/cp/decl2.c b/gcc/cp/decl2.c index b106710..b087753 100644 --- a/gcc/cp/decl2.c +++ b/gcc/cp/decl2.c @@ -2358,9 +2358,6 @@ min_vis_r (tree *tp, int *walk_subtrees, void *data) int this_vis = VISIBILITY_DEFAULT; if (! TYPE_P (*tp)) *walk_subtrees = 0; - else if (typedef_variant_p (*tp)) - /* Look through typedefs despite cp_walk_subtrees. */ - this_vis = type_visibility (DECL_ORIGINAL_TYPE (TYPE_NAME (*tp))); else if (OVERLOAD_TYPE_P (*tp) && !TREE_PUBLIC (TYPE_MAIN_DECL (*tp))) { @@ -2379,6 +2376,10 @@ min_vis_r (tree *tp, int *walk_subtrees, void *data) if (this_vis > *vis_p) *vis_p = this_vis; + /* Tell cp_walk_subtrees to look through typedefs. */ + if (*walk_subtrees == 1) + *walk_subtrees = 2; + return NULL; } diff --git a/gcc/cp/tree.c b/gcc/cp/tree.c index 82027cc..c536eb5 100644 --- a/gcc/cp/tree.c +++ b/gcc/cp/tree.c @@ -5146,16 +5146,26 @@ cp_walk_subtrees (tree *tp, int *walk_subtrees_p, walk_tree_fn func, if (TYPE_P (*tp)) { - /* Walk into template args without looking through typedefs. */ - if (tree ti = TYPE_TEMPLATE_INFO_MAYBE_ALIAS (*tp)) - WALK_SUBTREE (TI_ARGS (ti)); - /* Don't look through typedefs; walk_tree_fns that want to look through - typedefs (like min_vis_r) need to do that themselves. */ - if (typedef_variant_p (*tp)) + /* If *WALK_SUBTREES_P is 1, we're interested in the syntactic form of + the argument, so don't look through typedefs, but do walk into + template arguments for alias templates (and non-typedefed classes). + + If *WALK_SUBTREES_P > 1, we're interested in type identity or + equivalence, so look through typedefs, ignoring template arguments for + alias templates, and walk into template args of classes. + + See find_abi_tags_r for an example of setting *WALK_SUBTREES_P to 2 + when that's the behavior the walk_tree_fn wants. */ + if (*walk_subtrees_p == 1 && typedef_variant_p (*tp)) { + if (tree ti = TYPE_ALIAS_TEMPLATE_INFO (*tp)) + WALK_SUBTREE (TI_ARGS (ti)); *walk_subtrees_p = 0; return NULL_TREE; } + + if (tree ti = TYPE_TEMPLATE_INFO (*tp)) + WALK_SUBTREE (TI_ARGS (ti)); } /* Not one of the easy cases. We must explicitly go through the diff --git a/gcc/testsuite/g++.dg/abi/abi-tag24.C b/gcc/testsuite/g++.dg/abi/abi-tag24.C new file mode 100644 index 0000000..c758544 --- /dev/null +++ b/gcc/testsuite/g++.dg/abi/abi-tag24.C @@ -0,0 +1,17 @@ +// PR c++/98481 +// { dg-do compile { target c++11 } } +inline namespace N __attribute ((__abi_tag__ ("myabi"))) +{ + struct A {}; +} +template +struct B { typedef int size_type; }; +struct S1 { B::size_type foo () const { return 1; } }; +struct S2 { B::size_type foo () const; }; +int S2::foo () const { return 2; } +int (S1::*f1) () const = &S1::foo; +int (S2::*f2) () const = &S2::foo; + +// { dg-final { scan-assembler "_ZNK2S13fooEv" } } +// { dg-final { scan-assembler "_ZNK2S23fooEv" } } +// { dg-final { scan-assembler-not "_ZNK2S13fooB5myabiEv" } } -- 2.7.4