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8270 :: parallel: invalid control flow for 'parallel'

• veksha (orginal) [2021-07-26T14:47:04+02:00] view original

  Hello.

  I can compile the following code with gc:refc but not with gc:orc. Am I missing something? I had to use n.unsafeaddr for reasons unknown to me. who can shed some light on this for me? must be something special going on with for loop variable n.

  #[
  nim c -r --gc:refc --threads:on sometest
  nim c -r --gc:orc --threads:on sometest
  ]#
  
  {.experimental.}
  import json, threadpool
  
  proc job(node: ptr JsonNode) =
      echo node[].type # JsonNode
      let key1 = node[]["key"] # Error: invalid control flow for 'parallel'
  
  var nodes: JsonNode = parseJson("""
  { "res": [{"key":"val1"},{"key":"val2"}] } """)["res"]
  parallel:
      for n in nodes:
          spawn job(n.unsafeaddr)
  Run

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• veksha (orginal) [2021-07-26T15:14:53+02:00] view original

  for your information: nim 1.2.0 compiles this with ORC without errors. can this be a bug?

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• veksha (orginal) [2021-07-26T18:27:35+02:00] view original

  Interesting :

  #[
  nim c -r --gc:refc --threads:on sometest
  nim c -r --gc:orc --threads:on sometest
  ]#
  
  {.experimental.}
  import json, threadpool
  
  proc job(node: ptr JsonNode) =
  #    echo node
      let key1 = node[]["key"] # Error: invalid control flow for 'parallel'
      echo key1
  
  var nodes: JsonNode = parseJson("""
  { "res": [{"key":"val1"},{"key":"val2"}] } """)["res"]
  parallel:
      for n in nodes:
          spawn job(n.unsafeaddr)
  Run

  with refc - output is:

  
  "val1"
  "val2"
  Run

  with refc and uncommented line echo node:

  
  {"key":"val1"}
  {"key":"val2"}
  "val2"
  "val2"
  Run

  why val2 two times??

  with orc - not compiles - Error: invalid control flow for 'parallel'

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