[oe] [meta-python][rocko][PATCH] python-cryptography: add -pthread to LD_FLAGS

[Derek Straka]

The OpenSSL bindings require pthread to avoid runtime issues that end in stack traces:

File "/usr/lib/python2.7/site-packages/OpenSSL/__init__.py", line 8, in <module>
    from OpenSSL import crypto, SSL
  File "/usr/lib/python2.7/site-packages/OpenSSL/crypto.py", line 16, in <module>
    from OpenSSL._util import (
  File "/usr/lib/python2.7/site-packages/OpenSSL/_util.py", line 6, in <module>
    from cryptography.hazmat.bindings.openssl.binding import Binding
  File "/usr/lib/python2.7/site-packages/cryptography/hazmat/bindings/openssl/binding.py", line 13, in <module>
    from cryptography.hazmat.bindings._openssl import ffi, lib
ImportError: /usr/lib/python2.7/site-packages/cryptography/hazmat/bindings/_openssl.so: undefined symbol: pthread_atfork

[YOCTO #12339]

Signed-off-by: Derek Straka <derek at asterius.io>
---
 meta-python/recipes-devtools/python/python-cryptography.inc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/meta-python/recipes-devtools/python/python-cryptography.inc b/meta-python/recipes-devtools/python/python-cryptography.inc
index a4d1bbb..87ff16c 100644
--- a/meta-python/recipes-devtools/python/python-cryptography.inc
+++ b/meta-python/recipes-devtools/python/python-cryptography.inc
@@ -55,4 +55,6 @@ FILES_${PN}-dbg += " \
     ${libdir}/${PYTHON_PN}2.7/site-packages/${SRCNAME}/hazmat/bindings/.debug \
 "
 
+LDFLAGS_append = " -pthread"
+
 BBCLASSEXTEND = "native nativesdk"
-- 
2.7.4