From 3e52bb6535a70339cf4a15123be09916ef0c31f6 Mon Sep 17 00:00:00 2001
From: Zahary Karadjov <zahary@gmail.com>
Date: Tue, 18 Apr 2017 23:55:59 +0300
Subject: [PATCH] fix a regrsesion in signature matching of derived ptr types

---
 compiler/sigmatch.nim              |  8 +++++---
 tests/generics/tptrinheritance.nim | 20 ++++++++++++++++++++
 2 files changed, 25 insertions(+), 3 deletions(-)
 create mode 100644 tests/generics/tptrinheritance.nim

diff --git a/compiler/sigmatch.nim b/compiler/sigmatch.nim
index a8551fa194..d6a0c6382e 100644
--- a/compiler/sigmatch.nim
+++ b/compiler/sigmatch.nim
@@ -1240,13 +1240,15 @@ proc typeRel(c: var TCandidate, f, aOrig: PType, doBind = true): TTypeRelation =
         if prev == nil: put(c, f, a)
         result = isGeneric
       else:
-        var aAsObject = roota.lastSon
-        if rootf.lastSon.kind in {tyAnd, tyOr}:
+        let fKind = rootf.lastSon.kind
+        if fKind in {tyAnd, tyOr}:
           result = typeRel(c, lastSon(f), a)
           if result != isNone: put(c, f, a)
           return
 
-        if rootf.lastSon.kind == tyRef and aAsObject.kind == tyRef:
+        var aAsObject = roota.lastSon
+
+        if fKind in {tyRef, tyPtr} and aAsObject.kind == fKind:
           aAsObject = aAsObject.base
 
         if aAsObject.kind == tyObject:
diff --git a/tests/generics/tptrinheritance.nim b/tests/generics/tptrinheritance.nim
new file mode 100644
index 0000000000..1e1115fa56
--- /dev/null
+++ b/tests/generics/tptrinheritance.nim
@@ -0,0 +1,20 @@
+type NSPasteboardItem* = ptr object
+type NSPasteboard* = ptr object
+type NSArrayAbstract = ptr object {.inheritable.}
+type NSMutableArrayAbstract = ptr object of NSArrayAbstract
+type NSArray*[T] = ptr object of NSArrayAbstract
+type NSMutableArray*[T] = ptr object of NSArray[T]
+
+proc newMutableArrayAbstract*(): NSMutableArrayAbstract = discard
+
+template newMutableArray*(T: typedesc): NSMutableArray[T] =
+  cast[NSMutableArray[T]](newMutableArrayAbstract())
+
+proc writeObjects*(p: NSPasteboard, o: ptr NSArray[NSPasteboardItem]) = discard
+
+let a = newMutableArray NSPasteboardItem
+var x: NSMutableArray[NSPasteboardItem]
+var y: NSArray[NSPasteboardItem] = x
+
+writeObjects(nil, a)
+