Fix crash if delayed template parsing meets an erroneous trailing return type.
Based on a patch and test by Stephan Tolksdorf! Refactoring and fixing adjacent
brokenness by me.
llvm-svn: 203733
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 521fc3f..ec06285 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -9695,6 +9695,30 @@
const_cast<VarDecl*>(NRVOCandidate)->setNRVOVariable(true);
}
+bool Sema::canDelayFunctionBody(const Declarator &D) {
+ // We can't delay parsing the body of a constexpr function template (yet).
+ if (D.getDeclSpec().isConstexprSpecified())
+ return false;
+
+ // We can't delay parsing the body of a function template with a deduced
+ // return type (yet).
+ if (D.getDeclSpec().containsPlaceholderType()) {
+ // If the placeholder introduces a non-deduced trailing return type,
+ // we can still delay parsing it.
+ if (D.getNumTypeObjects()) {
+ const auto &Outer = D.getTypeObject(D.getNumTypeObjects() - 1);
+ if (Outer.Kind == DeclaratorChunk::Function &&
+ Outer.Fun.hasTrailingReturnType()) {
+ QualType Ty = GetTypeFromParser(Outer.Fun.getTrailingReturnType());
+ return Ty.isNull() || !Ty->isUndeducedType();
+ }
+ }
+ return false;
+ }
+
+ return true;
+}
+
bool Sema::canSkipFunctionBody(Decl *D) {
// We cannot skip the body of a function (or function template) which is
// constexpr, since we may need to evaluate its body in order to parse the