Couldn't compile: undefined reference to `CPU_ZERO' [Nim 1.4.8 only, works fine on 1.6.0]

[DavideGalilei]

This example fails to compile, saying undefined reference to `CPU_ZERO'

Example

import std/os

var t: Thread[void]

proc test = 
  while true:
    echo "in thread!"
    sleep(1000)

proc main = 
  createThread(t, test)
  pinToCpu(t, 2)
  while true:
    sleep(1000)

main()

Current Output

Compiler logs

davide@arch /t/tests> nim c -r --threads:on test.nim 
Hint: used config file '/home/davide/.choosenim/toolchains/nim-1.4.8/config/nim.cfg' [Conf]
Hint: used config file '/home/davide/.choosenim/toolchains/nim-1.4.8/config/config.nims' [Conf]
..................CC: stdlib_assertions.nim
CC: stdlib_locks.nim
CC: stdlib_sharedlist.nim
CC: stdlib_io.nim
CC: stdlib_system.nim
CC: stdlib_times.nim
CC: stdlib_os.nim
CC: test.nim

Hint:  [Link]
/usr/bin/ld: /home/davide/.cache/nim/test_d/stdlib_system.nim.c.o: in function `pinToCpu__cOvMVoT2TGICB4WVS7s5BA':
stdlib_system.nim.c:(.text+0xf817): undefined reference to `CPU_ZERO'
/usr/bin/ld: stdlib_system.nim.c:(.text+0xf836): undefined reference to `CPU_SET'
collect2: error: ld returned 1 exit status
Error: execution of an external program failed: 'gcc   -o /tmp/tests/test  /home/davide/.cache/nim/test_d/stdlib_assertions.nim.c.o /home/davide/.cache/nim/test_d/stdlib_locks.nim.c.o /home/davide/.cache/nim/test_d/stdlib_sharedlist.nim.c.o /home/davide/.cache/nim/test_d/stdlib_io.nim.c.o /home/davide/.cache/nim/test_d/stdlib_system.nim.c.o /home/davide/.cache/nim/test_d/stdlib_times.nim.c.o /home/davide/.cache/nim/test_d/stdlib_os.nim.c.o /home/davide/.cache/nim/test_d/@mtest.nim.c.o  -pthread -lm -lrt   -ldl'

Expected Output

Program should compile.

Possible Solution

• Compiling with nim c -r --threads:on --passC:-D_GNU_SOURCE test.nim works correctly (https://stackoverflow.com/questions/24034631/error-message-undefined-reference-for-cpu-zero/24034698)

Additional Information

It works fine on Nim 1.6.0, however it doesn't compile on 1.4.8. Tested on Arch Linux: Linux arch 5.14.12-arch1-1 #1 SMP PREEMPT Wed, 13 Oct 2021 16:58:16 +0000 x86_64 GNU/Linux

I installed Nim using choosenim.

$ nim -v
Nim Compiler Version 1.4.8 [Linux: amd64]
Compiled at 2021-05-25
Copyright (c) 2006-2021 by Andreas Rumpf

git hash: 44e653a9314e1b8503f0fa4a8a34c3380b26fff3
active boot switches: -d:release

$ choosenim show
  Selected: 1.6.0
   Channel: stable
      Path: /home/davide/.choosenim/toolchains/nim-1.6.0

  Versions:  
          * 1.6.0
            1.4.8
            0.15.2

[ringabout]

Nim 1.4.8 won't accept new patches. Nim 1.6.x is long term release and it works on 1.6.0.