As pointed out in the PR, we don't need base 'tor variants for a final
class, since it can never be a base. I tried also dropping complete
variants for abstract classes, but that runs into ABI compatibility problems
with older releases that refer to those symbols.
Tested x86_64-pc-linux-gnu, applying to trunk.
* optimize.c (populate_clone_array): Skip base variant if
CLASSTYPE_FINAL.
(maybe_clone_body): We don't need an alias if we are only defining
one clone.
---
gcc/cp/optimize.c | 12 ++++++++----
gcc/testsuite/g++.dg/other/final8.C | 9 +++++++++
gcc/cp/ChangeLog | 6 ++++++
3 files changed, 23 insertions(+), 4 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/other/final8.C
diff --git a/gcc/cp/optimize.c b/gcc/cp/optimize.c
index aace7dea684..0774857f503 100644
--- a/gcc/cp/optimize.c
+++ b/gcc/cp/optimize.c
@@ -247,15 +247,19 @@ populate_clone_array (tree fn, tree *fns)
fns[1] = NULL_TREE;
fns[2] = NULL_TREE;
- /* Look for the complete destructor which may be used to build the
- delete destructor. */
+ tree ctx = DECL_CONTEXT (fn);
+
FOR_EACH_CLONE (clone, fn)
if (DECL_NAME (clone) == complete_dtor_identifier
|| DECL_NAME (clone) == complete_ctor_identifier)
fns[1] = clone;
else if (DECL_NAME (clone) == base_dtor_identifier
|| DECL_NAME (clone) == base_ctor_identifier)
- fns[0] = clone;
+ {
+ /* We don't need to define the base variants for a final class. */
+ if (!CLASSTYPE_FINAL (ctx))
+ fns[0] = clone;
+ }
else if (DECL_NAME (clone) == deleting_dtor_identifier)
fns[2] = clone;
else
@@ -480,7 +484,7 @@ maybe_clone_body (tree fn)
/* Remember if we can't have multiple clones for some reason. We need to
check this before we remap local static initializers in clone_body. */
- if (!tree_versionable_function_p (fn))
+ if (!tree_versionable_function_p (fn) && fns[0] && fns[1])
need_alias = true;
/* We know that any clones immediately follow FN in the TYPE_FIELDS
diff --git a/gcc/testsuite/g++.dg/other/final8.C
b/gcc/testsuite/g++.dg/other/final8.C
new file mode 100644
index 00000000000..f90f94e9ea0
--- /dev/null
+++ b/gcc/testsuite/g++.dg/other/final8.C
@@ -0,0 +1,9 @@
+// { dg-do compile { target c++11 } }
+// { dg-final { scan-assembler-not "_ZN1BC2Ev" } }
+// { dg-final { scan-assembler-not "_ZN1BD2Ev" } }
+
+struct A { int i; A(); virtual ~A() = 0; };
+struct B final: public virtual A { int j; B(); ~B(); };
+
+B::B() {}
+B::~B() {}
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index dee69b87eba..9d89ccb4ab9 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,11 @@
2019-06-25 Jason Merrill <ja...@redhat.com>
+ PR c++/70462 - unnecessary base ctor variant with final.
+ * optimize.c (populate_clone_array): Skip base variant if
+ CLASSTYPE_FINAL.
+ (maybe_clone_body): We don't need an alias if we are only defining
+ one clone.
+
* class.c (resolves_to_fixed_type_p): Check CLASSTYPE_FINAL.
2019-06-25 Jakub Jelinek <ja...@redhat.com>
base-commit: 92c7d5c6805b9cdad3acf325d0569d563d5ea278
--
2.20.1
