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mirror of git://sourceware.org/git/newlib-cygwin.git synced 2025-02-24 01:29:34 +08:00
Jon Turney a30cd7a5b9
Cygwin: Remove waitloop argument from try_to_debug()
Currently, when using CYGWIN's error_start facility, the faulting
process isn't stopped while the error_start process is started when the
fault is caused by an exception. (it even seems possible in theory that
the faulting process could have exited before the error_start process
attaches).

This leads to e.g. the core dump written by CYGWIN='error_start=dumper'
in response to an exception being non-deterministic.

Remove the waitloop argument from try_to_debug(), only used in the
exception case, so the faulting process busy-waits until the error_start
process attaches.

Code archaeology to determine why the code is this way didn't really
turn up any answers, but this seems a low-risk change, as this only
changes the behaviour when:

 - a debugger isn't already attached
 - an error_start is specified in CYGWIN env var
 - an exception has occurred which will be translated to a signal

If error_start invokes something which doesn't attach using
DebugActiveProcess(), we will spin indefinitely, but that will also
currently occur for any of the existing other uses of try_to_debug(),
which default to waitloop=TRUE.
2020-08-30 16:24:47 +01:00
..
2020-08-30 14:27:43 +02:00

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