fix illegal recursion checks

compiler/types.nim

@@ -1144,8 +1144,10 @@ proc computeSizeAux(typ: PType, a: var biggestInt): biggestInt =
      tyBigNum: 
     result = ptrSize
     a = result
-  of tyArray, tyArrayConstr: 
-    result = lengthOrd(typ.sons[0]) * computeSizeAux(typ.sons[1], a)
+  of tyArray, tyArrayConstr:
+    let elemSize = computeSizeAux(typ.sons[1], a)
+    if elemSize < 0: return elemSize
+    result = lengthOrd(typ.sons[0]) * elemSize
   of tyEnum: 
     if firstOrd(typ) < 0: 
       result = 4              # use signed int32
@@ -1196,8 +1198,9 @@ proc computeSizeAux(typ: PType, a: var biggestInt): biggestInt =
   of tyGenericInst, tyDistinct, tyGenericBody, tyMutable, tyConst, tyIter:
     result = computeSizeAux(lastSon(typ), a)
   of tyTypeDesc:
-    result = (if typ.len == 1: computeSizeAux(typ.sons[0], a) else: -1)
-  of tyProxy: result = 1
+    result = if typ.len == 1: computeSizeAux(typ.sons[0], a)
+             else: szUnknownSize
+  of tyForward: return szIllegalRecursion
   else:
     #internalError("computeSizeAux()")
     result = szUnknownSize

tests/reject/tillrec.nim

@@ -3,15 +3,14 @@ discard """
   line: 13
   errormsg: "illegal recursion in type \'TIllegal\'"
 """
-# test illegal recursive types
-
-type
-  TLegal {.final.} = object
-    x: int
-    kids: seq[TLegal]
-
-  TIllegal {.final.} = object  #ERROR_MSG illegal recursion in type 'TIllegal'
-    y: Int
-    x: array[0..3, TIllegal]
+# test illegal recursive types
 
+type
+  TLegal {.final.} = object
+    x: int
+    kids: seq[TLegal]
+
+  TIllegal {.final.} = object  #ERROR_MSG illegal recursion in type 'TIllegal'
+    y: Int
+    x: array[0..3, TIllegal]
 

tests/reject/typredef.nim

@@ -3,8 +3,6 @@ discard """
   line: 7
   errormsg: "illegal recursion in type \'Uint8\'"
 """
-type
-  Uint8 = Uint8 #ERROR_MSG illegal recursion in type 'Uint8'
-
-
+type
+  Uint8 = Uint8 #ERROR_MSG illegal recursion in type 'Uint8'