Cygwin: cindex-dump.py segfaults under python2.7

[Quuxplusone]

Bugzilla Link	PR24039
Status	NEW
Importance	P normal
Reported by	brad_e@hotmail.com
Reported on	2015-07-06 11:25:42 -0700
Last modified on	2015-07-24 10:24:56 -0700
Version	3.5
Hardware	PC Windows NT
CC	geek4civic@gmail.com, llvm-bugs@lists.llvm.org
Fixed by commit(s)
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I'm not sure if this should be reported to Cygwin or here but I've been using
the Python bindings for libclang for a while. I updated last week to the latest
provided with Cygwin (3.5.2) and now I'm getting a segmentation fault when I
try to run the cindex-dump.py example script provided with the Python bindings.

python cindex-dump.py hello.c:

  #include <stdio.h>
  #include <stdlib.h>

  int main(void)
  {
      return 0;
  }

The version I'm using is:
    python-clang (3.5.2.1)

I'm running on a 64 bit version of Windows 7. The same problem happens on a 64
bit version of Windows 8.

The cindex-includes.py file runs correctly. I'm using the cindex-dump.py and
cindex-includes.py bundled with 3.5.2 from the LLVM downloads page.

I also tried downloading 3.6.1 and compiling it from source but the python
bindings again crash under Cygwin when I run cindex-dump.py.

[Quuxplusone]

The 32 bit version of Cygwin (on a 64 bit OS) doesn't seem to crash when I run
the Python bindings for libclang/cygclang so it must be something to do with
the 64 bit version. I don't see a crash but I end up with all kinds of forking
issues when I try to launch a process via subprocess. I've tried rebasing many
times but it doesn't seem to resolve the forking issue. It's at least a partial
solution to my problem.

[main] python2.7 3400 child_info_fork::abort: address space needed by 'c
ygfontconfig-1.dll' (0x1FC0000) is already occupied
(<type 'exceptions.OSError'>, OSError(11, 'Resource temporarily unavailable'),
<                                                                traceback
object at 0xffa95d9c>)
Traceback (most recent call last):

[Quuxplusone]

The command that I run in Cygwin is this:

  python cindex-dump.py hello.c
  Segmentation fault (core dumped)

This creates a python2.7.exe.stackdump file but I can't figure out how to get
anything useful from it as it appears I need to re-build Python with debug
symbols turned on.

The cindex-dump.py file comes from:
    http://llvm.org/svn/llvm-project/cfe/trunk/bindings/python/examples/cindex/cindex-dump.py

There don't appear to be any differences between version 3.5.2 (which it looks
like Cygwin is bundling) and the latest.

The hello.c file is pretty simple:

  #include <stdio.h>
  #include <stdlib.h>

  int main(void)
  {
    return 0;
  }