proc_waiter: error on read of child wait pipe 0x0, Win32 error 6

[Jay K]

Um, I know this isn't (yet) diligent/scientific, but must system create this thread?

#0  0x00007ff811e09e47 in KERNEL32!CreateThread () from /cygdrive/c/WINDOWS/System32/KERNEL32.DLL
#1  0x00000001800468eb in cygthread::create() () from /usr/bin/cygwin1.dll
#2  0x000000018010645f in pinfo::wait() () from /usr/bin/cygwin1.dll
#3  0x000000018012e562 in proc_subproc(unsigned int, unsigned long) () from /usr/bin/cygwin1.dll
#4  0x0000000180134e85 in child_info_spawn::worker(char const*, char const* const*, char const* const*, int, int, int) () from /usr/bin/cygwin1.dll
#5  0x0000000180136729 in spawnve () from /usr/bin/cygwin1.dll
#6  0x0000000180136d05 in spawnvp () from /usr/bin/cygwin1.dll
#7  0x0000000180144683 in system () from /usr/bin/cygwin1.dll
#8  0x000000018018effb in _sigfe () from /usr/bin/cygwin1.dll
#9  0x000000010052884b in QMachine__ExecCommand (t_L_563=0x448ef0 "\260\324\005",

'cause i.e. it complicates any lifetime/management.
I do understand some of the problems here, like needing separate threads to read stdout/stderr, if they are not equal.

 - Jay

________________________________
From: Jay K
Sent: Wednesday, January 12, 2022 4:12 AM
To: cygwin@sourceware.org <cygwin@sourceware.org>
Subject: proc_waiter: error on read of child wait pipe 0x0, Win32 error 6

I get this a lot:

      0 [waitproc] cm3 7641 proc_waiter: error on read of child wait pipe 0x0, Win32 error 6
    452 [waitproc] cm3 7641 proc_waiter: error on read of child wait pipe 0x0, Win32 error 6
    716 [waitproc] cm3 7641 proc_waiter: error on read of child wait pipe 0x0, Win32 error 6
   1652 [waitproc] cm3 7641 proc_waiter: error on read of child wait pipe 0x0, Win32 error 6
      0 [main] sh 7775 C:\cygwin64\bin\sh.exe: *** fatal error - internal error reading the windows environment - too many environment variables?

Scenario is multi-threaded "launching" a bunch of invocations of gcc.
"launching" was usually spawnve or fork/execve but I changed the code to use system and it still happens.
I might try to make a small reproducing, if this is not known.
It seems a bit difficult to believe I could cause this internal looking error.

Thank you,
 - Jay