[clang-cl] Fix PR38934: failing to dllexport class template member w/ explicit instantiation and PCH
The code in ASTContext::DeclMustBeEmitted was supposed to handle this,
but didn't take into account that synthesized members such as operator=
might not get marked as template specializations, because they're
synthesized on the instantiation directly when handling the class-level
dllexport attribute.
llvm-svn: 342240
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index b107e8b..3d0d1e6 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -9724,6 +9724,14 @@
cast<FunctionDecl>(D)->getTemplateSpecializationKind() ==
TSK_ExplicitInstantiationDefinition;
+ // Implicit member function definitions, such as operator= might not be
+ // marked as template specializations, since they're not coming from a
+ // template but synthesized directly on the class.
+ IsExpInstDef |=
+ isa<CXXMethodDecl>(D) &&
+ cast<CXXMethodDecl>(D)->getParent()->getTemplateSpecializationKind() ==
+ TSK_ExplicitInstantiationDefinition;
+
if (getExternalSource()->DeclIsFromPCHWithObjectFile(D) && !IsExpInstDef)
return false;
}
diff --git a/clang/test/CodeGen/pch-dllexport.cpp b/clang/test/CodeGen/pch-dllexport.cpp
index 9c6623b..b8db075 100644
--- a/clang/test/CodeGen/pch-dllexport.cpp
+++ b/clang/test/CodeGen/pch-dllexport.cpp
@@ -57,6 +57,13 @@
template <typename T> T __declspec(dllexport) variableTemplate;
extern template int variableTemplate<int>;
+namespace pr38934 {
+template <typename T> struct S {};
+extern template struct S<int>;
+// The use here causes the S<int>::operator= decl to go into the PCH.
+inline void use(S<int> *a, S<int> *b) { *a = *b; };
+}
+
#else
void use() {
@@ -81,4 +88,9 @@
template int __declspec(dllexport) variableTemplate<int>;
// PCHWITHOBJVARS: @"??$variableTemplate@H@@3HA" = weak_odr dso_local dllexport global
+// PR38934: Make sure S<int>::operator= gets emitted. While it itself isn't a
+// template specialization, its parent is.
+template struct __declspec(dllexport) pr38934::S<int>;
+// PCHWITHOBJ: define weak_odr dso_local dllexport x86_thiscallcc dereferenceable(1) %"struct.pr38934::S"* @"??4?$S@H@pr38934@@QAEAAU01@ABU01@@Z"
+
#endif