Decay the object expression of member accesses

Fixes #590

Signed-off-by: Roberto Raggi <[email protected]>

Author: robertoraggi

src/parser/cxx/type_checker.cc

@@ -2119,6 +2119,13 @@ auto TypeChecker::Visitor::check_member_access(MemberExpressionAST* ast)
   auto cv1 = strip_cv(objectType);
 
   if (ast->accessOp == TokenKind::T_MINUS_GREATER) {
+    if (control()->is_class_or_union(ast->baseExpression->type)) {
+      // todo: lookup operator-> in the class
+    } else {
+      (void)ensure_prvalue(ast->baseExpression);
+      objectType = ast->baseExpression->type;
+    }
+
     auto pointerType = type_cast<PointerType>(objectType);
     if (!pointerType) return false;
 

tests/unit_tests/sema/member_access_03.cc

@@ -0,0 +1,14 @@
+// RUN: %cxx -verify -fcheck -freport-missing-types %s
+
+struct X {
+  int a[1];
+};
+
+struct S {
+  struct X x[2];
+};
+
+int main() {
+  struct S s;
+  return s.x->a[0];
+}