cygwin1.dll 3.5.0-1 appears to cause spurious "error 127" with make 4.4.1

[Dimitry Andric]

Hi,

After a recent upgrade of a Cygwin installation, including cygwin1.dll
(see https://cygwin.com/pipermail/cygwin/2024-February/255308.html) to
3.5.0-1, I now get spurious "error 127" messages from (Cygwin's copy of)
GNU make 4.4.1-2, when it starts external processes and those external
processes exit with a zero exit code.

For example, a very simple Makefile:

all:
	cmd /c echo done

Running this a few times in a Cygwin bash prompt, gives:

  Dim@kilchoman ~/foobar
  $ make
  cmd /c echo done
  done

  Dim@kilchoman ~/foobar
  $ make
  cmd /c echo done
  done
  make: *** [Makefile:2: all] Error 127

  Dim@kilchoman ~/foobar
  $ make
  cmd /c echo done
  done

  Dim@kilchoman ~/foobar
  $ make
  cmd /c echo done
  done

  Dim@kilchoman ~/foobar
  $ make
  cmd /c echo done
  done
  make: *** [Makefile:2: all] Error 127

  Dim@kilchoman ~/foobar
  $ make
  cmd /c echo done
  done

  Dim@kilchoman ~/foobar
  $ make
  cmd /c echo done
  done

  Dim@kilchoman ~/foobar
  $ make
  cmd /c echo done
  done
  make: *** [Makefile:2: all] Error 127

  Dim@kilchoman ~/foobar
  $ make
  cmd /c echo done
  done

  Dim@kilchoman ~/foobar
  $ make
  cmd /c echo done
  done
  make: *** [Makefile:2: all] Error 127

So basically, every one in two or three runs randomly gives "error 127".
I have not yet figured out what is causing it, but any clue would be
nice!

In any case, reverting cygwin1.dll back to 3.4.10-1 immediately solves
the issue: I can then run this makefile in a loop for 10000 times, and
it will succeed every time.

Does anybody know if there are intermediate cygwin1.dll copies
somewhere, so I attempt to bisect where this problem started occurring?

-Dimitry