fix Issue 8836 - function called with argument types ((void function(…

…))) matches both f(void function() fn) and f(void delegate() dg)

src/cast.c

@@ -767,21 +767,20 @@ MATCH FuncExp::implicitConvTo(Type *t)
 {
     //printf("FuncExp::implicitConvTo type = %p %s, t = %s\n", type, type ? type->toChars() : NULL, t->toChars());
     Expression *e = inferType(t, 1);
-    if (e)
+    if (e &&
+        (t->ty == Tdelegate ||
+         t->ty == Tpointer && t->nextOf()->ty == Tfunction))
     {
         if (e != this)
             return e->implicitConvTo(t);
 
         /* MATCHconst:   Conversion from implicit to explicit function pointer
          * MATCHconvert: Conversion from impliict funciton pointer to delegate
          */
-        if (tok == TOKreserved && type->ty == Tpointer &&
-            (t->ty == Tpointer || t->ty == Tdelegate))
+        if (fd->tok == TOKreserved &&   // fbody doesn't have a frame pointer
+            (type->equals(t) || type->nextOf()->covariant(t->nextOf()) == 1))
         {
-            if (type == t)
-                return MATCHexact;
-            if (type->nextOf()->covariant(t->nextOf()) == 1)
-                return t->ty == Tpointer ? MATCHconst : MATCHconvert;
+            return t->ty == Tpointer ? MATCHconst : MATCHconvert;
         }
     }
     return Expression::implicitConvTo(t);

test/runnable/funclit.d

@@ -144,6 +144,8 @@ void tfun4c(T)(T f){}
 void test4()
 {
     int v;
+    static void sfoo() {}
+           void nfoo() {}
 
     // parameter type inference + overload resolution
     assert(foo4((a)   => a * 2) == 20);
@@ -158,8 +160,13 @@ void test4()
     // function/delegate inference + overload resolution
     assert(nbaz4({ }) == 1);
     assert(nbaz4({ v = 1; }) == 2);
+    assert(nbaz4({ sfoo(); }) == 1);    // Bugzilla 8836
+    assert(nbaz4({ nfoo(); }) == 2);
+
     assert(tbaz4({ }) == 1);
     assert(tbaz4({ v = 1; }) == 2);
+    assert(tbaz4({ sfoo(); }) == 1);
+    assert(tbaz4({ nfoo(); }) == 2);
 
     // template function deduction
     static assert(is(typeof(thoo4({ })) : void function()));