llvm::GlobalValue::LinkageTypes TargetLinkage =
getFunctionLinkage(TargetDecl);
- // available_externally definitions aren't real definitions, so we cannot
- // create an alias to one.
- if (TargetLinkage == llvm::GlobalValue::AvailableExternallyLinkage)
- return true;
-
// Check if we have it already.
StringRef MangledName = getMangledName(AliasDecl);
llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
// Instead of creating as alias to a linkonce_odr, replace all of the uses
// of the aliasee.
- if (llvm::GlobalValue::isDiscardableIfUnused(Linkage)) {
+ if (llvm::GlobalValue::isDiscardableIfUnused(Linkage) &&
+ (TargetLinkage != llvm::GlobalValue::AvailableExternallyLinkage ||
+ !TargetDecl.getDecl()->hasAttr<AlwaysInlineAttr>())) {
+ // FIXME: An extern template instantiation will create functions with
+ // linkage "AvailableExternally". In libc++, some classes also define
+ // members with attribute "AlwaysInline" and expect no reference to
+ // be generated. It is desirable to reenable this optimisation after
+ // corresponding LLVM changes.
addReplacement(MangledName, Aliasee);
return false;
}
+++ /dev/null
-// RUN: %clang_cc1 -O1 -std=c++11 -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s
-// Clang should not generate alias to available_externally definitions.
-// Check that the destructor of Foo is defined.
-// CHECK: define linkonce_odr void @_ZN3FooD2Ev
-template <class CharT>
-struct String {
- String() {}
- ~String();
-};
-
-template <class CharT>
-inline __attribute__((visibility("hidden"), always_inline))
-String<CharT>::~String() {}
-
-extern template struct String<char>;
-
-struct Foo : public String<char> { Foo() { String<char> s; } };
-
-Foo f;