When used with a build from source (i.e. non-installed) of Python,
get_python_lib gives the result (on Linux)

[prefix]/lib/python[version]

Shouldn't this be [prefix]/Lib?

Note that get_python_inc() returns "Include". That's because it makes
use of the "python_build" flag which is set for builds from source.

Yes, I agree with you, this may be a bug? 

Seemingly, the sysconfig.get_python_lib() should act just like the get_python_inc() function, return "[prefix]/lib/python[version]" in case of "python_build" flag is False, and "[prefix]/Lib" in case of "python_build" flag is True.

What ./configure line did you use?

Just plain

./configure

as far as I remember.

Can you propose a patch?  Also, can you say if the bug exists with the new sysconfig.get_path in 2.7 and 3.2?  (I can’t test right now, I ./configure with a --prefix, which logically gets used in the paths).

Attached is a patch for distutils/sysconfig.py.

Attached is a patch for sysconfig.py.

N.B. without the sysconfig.py patch, sysconfig.get_path() fails, but differently.

With the patch, sysconfig.get_path('stdlib') and sysconfig.get_path('include') give the expected values, but _CONFIG_VARS['srcdir'] still seems wrong:

vinay@eta-jaunty:/tmp$ python3.2
Python 3.2a2+ (py3k:84759, Sep 13 2010, 05:14:55) 
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sysconfig
>>> sysconfig._CONFIG_VARS['srcdir']
'/tmp'
>>> 

Someone please take a look!

The patches look good, thank you.  Do you have a command, script or test that would print the values, to make sure they’re right?

get_makefile_filename also fails when run from a checkout.

Attached is a simple script to show include and lib paths.

The makefile location seems OK on my system.

Actually, the makefile location *is* wrong - ignore my last comment contradicting that.

I’m not sure yet whether this is a bug or a new feature, but when python runs from an uninstalled build, I would like paths to refer to the source directory, not the default configure prefix.

See also #12141.

> I’m not sure yet whether this is a bug or a new feature, but when python runs from an
> uninstalled build, I would like paths to refer to the source directory, not the default
> configure prefix.

I need this fixed for packaging and it may affect venv too, so I will consider it a bug, fix it and wait for the python-dev response :)

Moving this back to patch review since I'm 90% sure that the patch won't apply anymore (if I had a little more time I'd pull it down and double check) - but I've hit this myself and would totally commit it if updated.

This issue still exists in Python 3.7.

Updated patch based on vinay.sajip's patch.

Updated patch based on vinay.sajip's patch.

These patches break both test_distutils & test_sysconfig tests.

Ok, so we need to figure out whether the tests are wrong, or the 'fix' is wrong.

Test output:

[cpython.25567]$ ./python.exe -m test test_distutils test_sysconfig -j3
Run tests in parallel using 3 child processes
0:00:01 [1/2/1] test_sysconfig failed
test test_sysconfig failed -- Traceback (most recent call last):
  File "/Users/kesara/pycon/cpython.25567/Lib/test/test_sysconfig.py", line 283, in test_user_similar
    self.assertEqual(user_path, global_path.replace(base, user, 1))
AssertionError: '/Users/kesara/.local/lib/python3.6' != '/Users/kesara/pycon/cpython.25567/Lib'
- /Users/kesara/.local/lib/python3.6
+ /Users/kesara/pycon/cpython.25567/Lib
0:00:05 [2/2/2] test_distutils failed
test test_distutils failed -- Traceback (most recent call last):
  File "/Users/kesara/pycon/cpython.25567/Lib/distutils/tests/test_sysconfig.py", line 40, in test_get_python_lib
    sysconfig.get_python_lib(prefix=TESTFN))
AssertionError: '/Users/kesara/pycon/cpython.25567/Lib' == '/Users/kesara/pycon/cpython.25567/Lib'

2 tests failed:
    test_distutils test_sysconfig

Total duration: 6 sec
Tests result: FAILURE

> Ok, so we need to figure out whether the tests are wrong, or the 'fix' is wrong.

The tests were never updated, so most likely they will need changing. I was waiting for feedback about my point about _CONFIG_VARS['srcdir'], but I never got any at the time ... will look at updating the patch with updated tests.

Updated patch to cover tests, and changed the implementation slightly. Tests pass on Linux and Windows (I'm not able to build on OS X). The patch is against the default branch but the diff should apply equally well to 3.6.

fix-6087.diff passes on OSX (Python 3.6)

$ ./python.exe -m test test_distutils test_sysconfig -j3
Run tests in parallel using 3 child processes
0:00:01 [1/2] test_sysconfig passed
0:00:13 [2/2] test_distutils passed
All 2 tests OK.

Total duration: 14 sec
Tests result: SUCCESS

Distutils is now deprecated (see PEP 632) and all tagged issues are being closed. From now until removal, only release blocking issues will be considered for distutils.

If this issue does not relate to distutils, please remove the component and reopen it. If you believe it still requires a fix, most likely the issue should be re-reported at https://github.com/pypa/setuptools