fixes #14079 [backport:1.2] (#14163)

tests/arc/tarcmisc.nim

@@ -46,7 +46,7 @@ type
 proc `=destroy`(x: var AObj) =
   close(x.io)
   echo "closed"
-  
+
 var x = B(io: newStringStream("thestream"))
 
 
@@ -64,4 +64,14 @@ proc main() =
   cryptCTR(nonce2.toOpenArray(0, nonce2.len-1))
   doAssert(nonce2 == "0A234567")
 
-main()
+main()
+
+# bug #14079
+import std/algorithm
+
+let
+  n = @["c", "b"]
+  q = @[("c", "2"), ("b", "1")]
+
+assert n.sortedByIt(it) == @["b", "c"], "fine"
+assert q.sortedByIt(it[0]) == @[("b", "1"), ("c", "2")], "fails under arc"

tests/arc/twrong_sinkinference.nim

@@ -0,0 +1,18 @@
+discard """
+  cmd: "nim c --gc:arc $file"
+  errormsg: "type mismatch: got <proc (a: string, b: sink string){.noSideEffect, gcsafe, locks: 0.}>"
+  line: 18
+"""
+
+type
+  Foo = proc (a, b: string)
+
+proc take(x: Foo) =
+  x("a", "b")
+
+proc willSink(a, b: string) = # {.nosinks.} =
+  var arr: array[3, string]
+  var x = a
+  arr[0] = b
+
+take willSink