[OE-core] python-native and autotools

[Randy MacLeod]

autoconf and automake build as part of the "core" tools that get built 
before any target packages are built whereas python-native isn't in
that set. When automake runs, it uses whatever python it finds.
This will be the python-native version if it has been built. When
doing parallel builds, it is possible to be building the python-native
while automake is running for some other package.  This can cause a
build failure with a signature such as:

   NOTE: package freetype-2.4.9-r0: task do_configure: Succeeded
   NOTE: Running task 1891 of 4319 (ID: 3642, /.../oe-core/meta/
   recipes-graphics/freetype/freetype_2.4.9.bb, do_compile)
   NOTE: Running task 1892 of 4319 (ID: 2327, /.../oe-core/meta/
   recipes-extended/zypper/zypper_git.bb, do_populate_lic)
   ERROR: Function failed: do_configure (see /.../tmp/work/
   x86_64-linux/guile-native-2.0.3-r5/temp/do_configure
   /log.do_configure.1659 for further information)
   ...
   Log data follows:
   | DEBUG: Executing python function sysroot_cleansstate
   | DEBUG: Python function sysroot_cleansstate finished
   --
   | python: error while loading shared libraries: libpython2.7.so.1.0:
   cannot open shared object file: No such file or directory
   | ERROR: Function failed: do_configure (see /.../tmp/work/
   x86_64-linux/guile-native-2.0.3-r5/temp/do_configure
   /log.do_configure.1659 for further information)
   NOTE: package guile-native-2.0.3-r5: task do_configure: Failed
   ...

Other signatures involve missing python files, such as:
   .../tmp/sysroots/x86_64-linux/usr/lib/python2.7/warnings.py",
   line 6, in <module>
     import linecache
   ImportError: No module named linecache

Changing the python install to be atomic might cover this up but
that isn't a very satisfying solution. It would be nice to make
anything that USES autotools depend on python-native, but this
causes problems because autoconf and automake inherit the autotools
class, so they would wind up depending on python, which, itself
inherits autotools.

A solution might be to have autoconf and automake and python inherit a 
version of autotools that does not add a python-native dependency, say
autotools-no-python, and then modify the "real" autotools class to
add the python dependency.

My build stats show that this problem
happens in less than 1 out of 40 builds with:
BB_NUMBER_THREADS = "20"
PARALLEL_MAKE = "-j 20"
Has anyone else seen this problem?

I'm still coming up to speed on bitbake's bootstrap process so
any suggestions would be appreciated.


-- 
# Randy MacLeod. MTS, Linux, Wind River
Direct: 613.963.1350