Template instantiation for GNU statement expressions

llvm-svn: 72129

clang/lib/Sema/SemaTemplateInstantiateExpr.cpp

@@ -54,6 +54,8 @@ namespace {
     OwningExprResult VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E);
     OwningExprResult VisitCXXConditionDeclExpr(CXXConditionDeclExpr *E);
     OwningExprResult VisitConditionalOperator(ConditionalOperator *E);
+    // FIXME: AddrLabelExpr
+    OwningExprResult VisitStmtExpr(StmtExpr *E);
     OwningExprResult VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E);
     OwningExprResult VisitUnresolvedDeclRefExpr(UnresolvedDeclRefExpr *E);
     OwningExprResult VisitCXXTemporaryObjectExpr(CXXTemporaryObjectExpr *E);
@@ -453,6 +455,16 @@ TemplateExprInstantiator::VisitConditionalOperator(ConditionalOperator *E) {
                                     move(Cond), move(LHS), move(RHS));
 }
 
+Sema::OwningExprResult TemplateExprInstantiator::VisitStmtExpr(StmtExpr *E) {
+  Sema::OwningStmtResult SubStmt = SemaRef.InstantiateStmt(E->getSubStmt(),
+                                                           TemplateArgs);
+  if (SubStmt.isInvalid())
+    return SemaRef.ExprError();
+  
+  return SemaRef.ActOnStmtExpr(E->getLParenLoc(), move(SubStmt),
+                               E->getRParenLoc());
+}
+
 Sema::OwningExprResult 
 TemplateExprInstantiator::VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E) {
   bool isSizeOf = E->isSizeOf();

clang/test/SemaTemplate/instantiate-expr-3.cpp

@@ -56,3 +56,16 @@ struct Conditional0 {
 };
 
 template struct Conditional0<int, int, int>;
+
+// ---------------------------------------------------------------------
+// Statement expressions
+// ---------------------------------------------------------------------
+template<typename T>
+struct StatementExpr0 {
+  void f(T t) {
+    (void)({ if (t) t = t + 17; }); // expected-error{{invalid}}
+  }
+};
+
+template struct StatementExpr0<int>;
+template struct StatementExpr0<N1::X>; // expected-note{{instantiation}}