Maybe it's just me, but could we please clarify in the test plan exactly what flag changes are we expecting? Given the change is to honor or not the "OPT" flags, I was expecting an additional test plan that would set those, and then show that they are included when the workaround var is set. That's much easier to verify.
Keep the tests you have, please, but what do you think about this extra test? It would clearly show when OPT is used and not. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to python2.7 in Ubuntu. https://bugs.launchpad.net/bugs/2002043 Title: Python extension modules get built using wrong compiler flags with python2 Status in python2.7 package in Ubuntu: Invalid Status in python2.7 source package in Bionic: Won't Fix Status in python2.7 source package in Focal: In Progress Status in python2.7 source package in Jammy: Fix Committed Status in python2.7 source package in Kinetic: Invalid Status in python2.7 source package in Lunar: Invalid Status in python2.7 source package in Mantic: Invalid Bug description: [ Impact ] When compiling Python extensions using Python2, CFLAGS optimization flags are dropped. This behavior has been caused by our update in this patch http://archive.ubuntu.com/ubuntu/pool/universe/p/python2.7/python2.7_2.7.18-1~20.04.3.diff.gz which differs from upstream. The fix modifies the portion of code in Lib/distutils/sysconfig.py which gets the cflags from the environments, and includes the dropped OPT flag from get_config_vars(). [ Test Plan ] There will be 2 separate tests for this bug: * Ensuring no-change rebuilds are not changed * Ensuring local builds are not changed unless environment variable is set Test 1) No-change rebuilds To test that no-change rebuilds are not changed, the package python- stdlib-extensions will be built against the new python2.7, and confirm the compiler flags are not altered. This will be a manual test and visual inspection of the build logs. Test 2) Functional test 1. Create test container $ lxc launch ubuntu:jammy jammy-2002043 $ lxc shell ubuntu:jammy jammy-2002043 2. Install required packages For Jammy # apt update -y && apt install -y python2 python-pip For Focal # apt update -y && apt install -y python2 python-setuptools 3. Create test files # mkdir testprog # cd testprog # cat >setup.py <<EOL from setuptools import setup, Extension setup( name="test", ext_modules=[Extension("test", sources=["testmodule.c"])], zip_safe=False ) EOL # cat >testmodule.c <<EOL #include <stdio.h> int main(void) { printf("This is test program"); return 0; } EOL 4. Compile a test program # python2 setup.py build_ext --inplace 5. Check CFLAGS # python2 -c "import sysconfig; print(sysconfig.get_config_var('CFLAGS'))" -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -Wdate-time -D_FORTIFY_SOURCE=2 -g -ffile-prefix-map=/build/python2.7-W40Ff2/python2.7-2.7.18=. -flto=auto -ffat-lto-objects -flto=auto -ffat-lto-objects -fstack-protector-strong -Wformat -Werror=format-security 6. Check the flags used to compile the test wheel # strings build/lib.linux-x86_64-2.7/test.so | grep -- -O GNU GIMPLE 11.4.0 -mtune=generic -march=x86-64 -g -g -g -g -O2 -fno-openmp -fno-openacc -fcf-protection=full -fno-strict-aliasing -fwrapv -fstack-protector-strong -ffat-lto-objects -fstack-protector-strong -fPIC -fltrans 7. Install fixed python Once updated, this will simply be an apt update && apt upgrade # add-apt-repository ppa:mitchdz/python2.7-optimization-flags -y # apt install -y python2.7 # dpkg -s python2.7 | grep Version: Version: 2.7.18-13ubuntu1.2~jammy9 8. Clean build # rm -rf build/ test.so 9. Enable opt-in environment variable # export APPLY_LP2002043_UBUNTU_CFLAGS_WORKAROUND="" 9. Rebuild with new python2.7 installed # python2 setup.py build_ext --inplace 10. Check build flags # strings build/lib.linux-x86_64-2.7/test.so | grep -- -O GNU GIMPLE 11.4.0 -mtune=generic -march=x86-64 -g -g -g -g -O2 -O2 -fno-openmp -fno-openacc -fcf-protection=full -fno-strict-aliasing -fwrapv -fstack-protector-strong -ffat-lto-objects -fstack-protector-strong -fPIC -fltrans GNU C17 11.4.0 -mtune=generic -march=x86-64 -g -g -O2 -fno-strict-aliasing -fwrapv -flto -flto -ffat-lto-objects -fstack-protector-strong -fPIC -fasynchronous-unwind-tables -fstack-protector-strong -fstack-clash-protection -fcf-protection [ Where problems could occur ] * Changing optimization flags can cause a myriad of unattended side effects, but the change being opt-in means the users should be aware a change is being made * The change is opt-in, so an informative message is printed to the console to spread awareness of the issue and how to use the workaround. A questionably made CI/CD system might see the new console output and flag it as a failure, so it is important to choose wording carefully. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/python2.7/+bug/2002043/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
