Problem with the create* API of synchronization primitives

[planetis-m]

The following code gives the error message: Error: '=sink' is not available for type <Semaphore>; routine: main

const
  N = 2

var
  arrived: array[N, Semaphore]

proc main =
  for i in 0 ..< N:
    arrived[i] = createSemaphore()
main()

[planetis-m]

However if we used:

proc init*(s: out Semaphore; count = 0) =
  s.counter = count
  initCond(s.c)
  initLock(s.L)

That wouldn't be an issue.

[planetis-m]

From the chat

you cannot "move" a pthread mutex but Nim's notion of a move is different from the idea "tied to its stack location"

disabling =sink is an ABI problem but we don't want semantic checking to depend on the ABI. We need to teach the code generator that a disabled =sink means "pass by pointer"

or we keep using .byref

ok so remove =sink .error?

patch the compiler so that let x = f() works for type T if T is byref