some love for the testsuite; fixed regressions

tests/ccgbugs/tmissingderef.nim

@@ -0,0 +1,30 @@
+discard """
+  output: '''255
+1 1
+0.5'''
+"""
+
+# bug #1181
+
+type
+  TFoo = object
+    x: int32
+
+proc mainowar =
+  var foo: TFoo
+  foo.x = 0xff
+  var arr1 = cast[ptr array[4, uint8]](addr foo)[] # Fails.
+  echo arr1[when cpuEndian == littleEndian: 0 else: 3]
+
+  var i = 1i32
+  let x = addr i
+  var arr2 = cast[ptr array[4, uint8]](x)[] # Fails.
+  echo arr2[when cpuEndian == littleEndian: 0 else: 3], " ", i
+
+  # bug #1715
+  var a: array[2, float32] = [0.5'f32, 0.7]
+  let p = addr a
+  var b = p[]
+  echo b[0]
+
+mainowar()