[MS] Mark default args of exported default constructors as used
Fixes a regression introduced in r291045, which would lead to link
errors. While we should no longer encounter unparsed or uninstantiated
default arguments in this codepath, we still need to call
CheckCXXDefaultArgExpr to mark the default argument expressions as
ODR-used.
llvm-svn: 291453
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 02b73e9..a70e16c 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -5395,13 +5395,31 @@
}
}
-static void checkForMultipleExportedDefaultConstructors(Sema &S, CXXRecordDecl *Class) {
+static void checkForMultipleExportedDefaultConstructors(Sema &S,
+ CXXRecordDecl *Class) {
+ // Only the MS ABI has default constructor closures, so we don't need to do
+ // this semantic checking anywhere else.
+ if (!S.Context.getTargetInfo().getCXXABI().isMicrosoft())
+ return;
+
CXXConstructorDecl *LastExportedDefaultCtor = nullptr;
for (Decl *Member : Class->decls()) {
// Look for exported default constructors.
auto *CD = dyn_cast<CXXConstructorDecl>(Member);
- if (!CD || !CD->isDefaultConstructor() || !CD->hasAttr<DLLExportAttr>())
+ if (!CD || !CD->isDefaultConstructor())
continue;
+ auto *Attr = CD->getAttr<DLLExportAttr>();
+ if (!Attr)
+ continue;
+
+ // If the class is non-dependent, mark the default arguments as ODR-used so
+ // that we can properly codegen the constructor closure.
+ if (!Class->isDependentContext()) {
+ for (ParmVarDecl *PD : CD->parameters()) {
+ (void)S.CheckCXXDefaultArgExpr(Attr->getLocation(), CD, PD);
+ S.DiscardCleanupsInEvaluationContext();
+ }
+ }
if (LastExportedDefaultCtor) {
S.Diag(LastExportedDefaultCtor->getLocation(),