fix Issue 9284 - DMD segfaults with templated ctors in constructor de…

…legation

src/expression.c

@@ -8334,6 +8334,8 @@ Expression *CallExp::semantic(Scope *sc)
             }
 
             f = resolveFuncCall(sc, loc, cd->ctor, NULL, NULL, arguments, 0);
+            if (!f)
+                return new ErrorExp();
             checkDeprecated(sc, f);
 #if DMDV2
             checkPurity(sc, f);

test/fail_compilation/ice9284.d

@@ -0,0 +1,22 @@
+/*
+TEST_OUTPUT:
+---
+fail_compilation/ice9284.d(15): Error: template ice9284.C.__ctor does not match any function template declaration. Candidates are:
+fail_compilation/ice9284.d(13):        ice9284.C.__ctor()(string)
+fail_compilation/ice9284.d(15): Error: template ice9284.C.__ctor()(string) cannot deduce template function from argument types !()(int)
+fail_compilation/ice9284.d(21): Error: template instance ice9284.C.__ctor!() error instantiating
+---
+*/
+
+class C
+{
+    this()(string)
+    {
+        this(10);
+        // delegating to a constructor which not exists.
+    }
+}
+void main()
+{
+    new C("hello");
+}