c++: Add ABI version for PR98481 fix

The PR98481 fix corrects an ABI regression in GCC 10, but we don't want to
introduce an ABI change in the middle of the GCC 10 cycle.  This patch
introduces ABI v15 for the fix, which will be available but not default in
GCC 10.3; the broken behavior remains in ABI v14.  Compatibility aliases
will not be generated for this change.

gcc/ChangeLog:

	PR c++/98481
	* common.opt: Document v15 and v16.

gcc/c-family/ChangeLog:

	PR c++/98481
	* c-opts.c (c_common_post_options): Bump latest_abi_version.

gcc/cp/ChangeLog:

	PR c++/98481
	* mangle.c (write_expression): Adjust.
	* class.c (find_abi_tags_r): Disable PR98481 fix for ABI v14.
	(mark_abi_tags_r): Likewise.

gcc/testsuite/ChangeLog:

	PR c++/98481
	* g++.dg/abi/abi-tag24a.C: New test.
	* g++.dg/abi/macro0.C: Adjust expected value.

diff --git a/gcc/c-family/c-opts.c b/gcc/c-family/c-opts.c
index bd15b9cd902d7b5f3d9d24e174b8fdb6d03b1e1c..89e05a4c55181e211f6ffe917beddcc25aae580e 100644 (file)
--- a/gcc/c-family/c-opts.c
+++ b/gcc/c-family/c-opts.c
@@ -965,7 +965,7 @@ c_common_post_options (const char **pfilename)
 
   /* Change flag_abi_version to be the actual current ABI level, for the
      benefit of c_cpp_builtins, and to make comparison simpler.  */
-  const int latest_abi_version = 15;
+  const int latest_abi_version = 16;
   /* Generate compatibility aliases for ABI v11 (7.1) by default.  */
   const int abi_compat_default = 11;
 

diff --git a/gcc/common.opt b/gcc/common.opt
index c75dd36843e2fb9746938e68f22c2332d62e522d..a75b44ee47e7016966143c6587ad798b47285286 100644 (file)
--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -960,7 +960,11 @@ Driver Undocumented
 ; 14: Corrects the mangling of nullptr expression.
 ;     Default in G++ 10.
 ;
-; 15: Changes the mangling of __alignof__ to be distinct from that of alignof.
+; 15: Corrects G++ 10 ABI tag regression [PR98481].
+;     Available, but not default, in G++ 10.3.
+;
+; 16: Changes the mangling of __alignof__ to be distinct from that of alignof.
+;     Adds missing 'on' in mangling of operator names in some cases.
 ;     Default in G++ 11.
 ;
 ; Additional positive integers will be assigned as new versions of

diff --git a/gcc/cp/class.c b/gcc/cp/class.c
index 856e81e3d1ab1955a51e59d774e722e7319e947f..4bffec4a707d0ccb4d4efc423c68aca6911aaf49 100644 (file)
--- a/gcc/cp/class.c
+++ b/gcc/cp/class.c
@@ -1494,8 +1494,8 @@ 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.  */
+  if (TYPE_P (*tp) && *walk_subtrees == 1 && flag_abi_version != 14)
+    /* Tell cp_walk_subtrees to look though typedefs. [PR98481] */
     *walk_subtrees = 2;
 
   if (!OVERLOAD_TYPE_P (*tp))
@@ -1518,7 +1518,7 @@ 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)
+  if (TYPE_P (*tp) && *walk_subtrees == 1 && flag_abi_version != 14)
     /* Tell cp_walk_subtrees to look though typedefs.  */
     *walk_subtrees = 2;
 

diff --git a/gcc/cp/mangle.c b/gcc/cp/mangle.c
index 57ce9a6710f26d0d0017bd093db7bb7fc67b7047..6c111342b9703bbcfe5ca3620b2acf27d908c8bc 100644 (file)
--- a/gcc/cp/mangle.c
+++ b/gcc/cp/mangle.c
@@ -3119,9 +3119,9 @@ write_expression (tree expr)
     {
       if (!ALIGNOF_EXPR_STD_P (expr))
        {
-         if (abi_warn_or_compat_version_crosses (15))
+         if (abi_warn_or_compat_version_crosses (16))
            G.need_abi_warning = true;
-         if (abi_version_at_least (15))
+         if (abi_version_at_least (16))
            {
              /* We used to mangle __alignof__ like alignof.  */
              write_string ("u11__alignof__");
@@ -3350,9 +3350,9 @@ write_expression (tree expr)
       tree name = dependent_name (expr);
       if (IDENTIFIER_ANY_OP_P (name))
        {
-         if (abi_version_at_least (15))
+         if (abi_version_at_least (16))
            write_string ("on");
-         if (abi_warn_or_compat_version_crosses (15))
+         if (abi_warn_or_compat_version_crosses (16))
            G.need_abi_warning = 1;
        }
       write_unqualified_id (name);

diff --git a/gcc/testsuite/g++.dg/abi/abi-tag24a.C b/gcc/testsuite/g++.dg/abi/abi-tag24a.C
new file mode 100644 (file)
index 0000000..83f930d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/abi/abi-tag24a.C
@@ -0,0 +1,18 @@
+// PR c++/98481
+// { dg-do compile { target c++11 } }
+// { dg-additional-options -fabi-version=14 }
+inline namespace N __attribute ((__abi_tag__ ("myabi")))
+{
+  struct A {};
+}
+template <typename T>
+struct B { typedef int size_type; };
+struct S1 { B<A>::size_type foo () const { return 1; } };
+struct S2 { B<A>::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-not "_ZNK2S13fooEv" } }
+// { dg-final { scan-assembler "_ZNK2S23fooEv" } }
+// { dg-final { scan-assembler "_ZNK2S13fooB5myabiEv" } }

diff --git a/gcc/testsuite/g++.dg/abi/macro0.C b/gcc/testsuite/g++.dg/abi/macro0.C
index 7c3c17051ed6ad60b2c770b7828627901a42039a..f25f291dba671d41b3f0f3b8f2ea8c01e1b4cbdc 100644 (file)
--- a/gcc/testsuite/g++.dg/abi/macro0.C
+++ b/gcc/testsuite/g++.dg/abi/macro0.C
@@ -1,6 +1,6 @@
 // This testcase will need to be kept in sync with c_common_post_options.
 // { dg-options "-fabi-version=0" }
 
-#if __GXX_ABI_VERSION != 1015
+#if __GXX_ABI_VERSION != 1016
 #error "Incorrect value of __GXX_ABI_VERSION"
 #endif