Author wes.kerfoot
Recipients amaury.forgeotdarc, belopolsky, meador.inge, wes.kerfoot
Date 2014-08-08.04:53:57
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python 2.7.8 fails with a 'stack smashing detected' error and aborts when trying to access a C union using ctypes/libffi

Steps to reproduce:
See the contents of test.c and in the attached file
gcc -c -fpic -Wall -Wextra -pedantic -Wpointer-arith -Werror -std=c99 -O0 ./test.c -o test.o
gcc -shared -o test.o

Also fails with clang instead of gcc.

OS: Linux frege 3.15.8-1-ARCH #1 SMP PREEMPT Fri Aug 1 08:51:42 CEST 2014 x86_64 GNU/Linux
python2 version: 2.7.8
libffi version (OS wide version): 3.1-2
gcc version: 4.9.1
clang version: 3.4.2

I have tried rebuilding python with the included version of libffi (Arch normally uses a systemwide version).

Here is the PKGBUILD file Arch uses

I have also reported this bug on their tracker since I am not sure if this is a bug in ctypes or libffi or both:
Date User Action Args
2014-08-08 04:53:59wes.kerfootsetrecipients: + wes.kerfoot, amaury.forgeotdarc, belopolsky, meador.inge
2014-08-08 04:53:59wes.kerfootsetmessageid: <>
2014-08-08 04:53:59wes.kerfootlinkissue22171 messages
2014-08-08 04:53:58wes.kerfootcreate