Add support for Python 3.7

[tomviner]

Python 3.7 is out now, and so it would be great to support it.

After adding the new deadsnakes ppa I submitted in #150 I discovered that we need to run the tests on Xenial for Python 3.7 to work. See travis-ci/travis-ci#9069 (comment)

As a user (but not developer) of pyflame this is basically as far as I've got. I tried catching Python 3.7 and applying the 3.6 ABI but that's just guess work.

Currently:

18 failed, 19 passed

Hopefully someone with some pyflame dev experience can have a go at getting it working :-)

See:

• Travis Job for by Python 3.7 branch: https://travis-ci.org/tomviner/pyflame/builds/403996654
• My branch: master...tomviner:python3.7-support

[altendky]

Mostly adding this so it might show up in searches for the error. 3.6 is nicely reported as unsupported but 3.7 fails with an error suggesting a ptrace configuration issue (at least per #120 where searches for the error lead you).

altendky@lt:~$ git -C pyflame rev-parse HEAD
d67c353b13b6950b48bbb8fcb1dde498637a4e28
altendky@lt:~$ pyflame/src/pyflame --version
pyflame 1.6.6 linux-gnu x86_64 (ABI list: 26 34)
altendky@lt:~$ cat /proc/sys/kernel/yama/ptrace_scope
0
altendky@lt:~$ pyflame/src/pyflame -o outfile -t python3.7 -c 'import time; time.sleep(5)'
Failed to locate libpython within timeout period.
altendky@lt:~$ pyflame/src/pyflame -o outfile -t python3.6 -c 'import time; time.sleep(5)'
Target has Python ABI 36, which is not supported by this pyflame build.
altendky@lt:~$ pyflame/src/pyflame -o outfile -t python3.5 -c 'import time; time.sleep(5)'
altendky@lt:~$ pyflame/src/pyflame -o outfile -t python3.4 -c 'import time; time.sleep(5)'
altendky@lt:~$ pyflame/src/pyflame -o outfile -t python2.7 -c 'import time; time.sleep(5)'
altendky@lt:~$

Note that 2.7/3.4/3.5 did run for five seconds as expected prior to completing.

[rim-odoo]

I'm also facing the Failed to locate libpython within timeout period. when running Python 3.7.2

[ganiganesh92]

I am trying to attach python app running on pypy env i am also facing same issue can any one help here...

[randomstuff]

For 3.7, there is no _PyThreadState_Current symbol anymore.

#  define _PyThreadState_Current _PyRuntime.gilstate.tstate_current 

[rpodgorny]

...any progress on this? i see many forks with python3.7 support but not a single pull request merged... :-(

[DapengNi]

I got same error "Failed to locate libpython within timeout period" on Ubuntu18.04 + Python 3.7 Gunicorn. It works all configurations are same but python2.7.

Can anyone make Pyflame working with 3.7? @randomstuff looks give some hint, but I cannot figure out how as I have minor knowledge on C/C++ code.