add tests

tests/misc/trfc_276.nim

@@ -7,7 +7,7 @@ proc test1 =
   doAssert a == 2
 test1()
 
-static:
+static: # bug #10938
   for i in '1' .. '2':
     var s: set[char]
     doAssert s == {}
@@ -41,27 +41,74 @@ block:
   const
     foo = cast[Fn](0)
 
-block:
+block: # bug #13918
   const test = block:
     var s = ""
     for i in 1 .. 5:
       var arr: array[3, int]
       var val: int
-      # echo arr, " ", val
       s.add $arr & " " & $val
       for j in 0 ..< len(arr):
         arr[j] = i
         val = i
     s
   doAssert test == "[0, 0, 0] 0[0, 0, 0] 0[0, 0, 0] 0[0, 0, 0] 0[0, 0, 0] 0"
 
-block:
+block: # bug #13312
   static:
     for _ in 0 ..< 3:
       var s: string
       s.add("foo")
       assert s == "foo"
 
+block: # bug #13887
+  static: # https://github.com/nim-lang/Nim/issues/13887#issuecomment-655829572
+    var x = 5
+    var y = addr(x)
+    y[] += 10
+    doAssert x == y[]
+
+  block: # Example 1
+    template fun() =
+      var s = @[10,11,12]
+      let z = s[0].addr
+      doAssert z[] == 10
+      z[] = 100
+      doAssert z[] == 100
+      doAssert s[0] == 100 # was failing here
+    static: fun() # was failing here
+    fun() # was working
+
+  block: # Example 2
+    template fun() =
+      var s = @[10,11,12]
+      let a1 = cast[int](s[0].addr) # 4323682360
+      let z = s[0].addr 
+      let a2 = cast[int](z) # 10 => BUG
+      doAssert a1 == a2
+    static: fun() # fails
+
+  block: # Example 3
+    template fun() =
+      var s = @[10.1,11.2,12.3]
+      let a1 = cast[int](s[0].addr)
+      let z = s[0].addr
+      let a2 = cast[int](z)
+    static: fun()
+
+block: # bug #12172
+  const a = block:
+    var test: array[5, string]
+    test
+  proc test =
+    const a2 = block:
+      var test: array[5, string] # was error here
+      test
+  proc test2 =
+    const a3 = block:
+      let i = 0 # Error here too
+      i
+
 when false:
   # xxx this doesn't work yet
   block: