package/python/008-distutils-use-python-sysroot.patch

   1 Adjust library/header paths for cross-compilation
   2
   3 When cross-compiling third-party extensions, the get_python_inc() or
   4 get_python_lib() can be called, to return the path to headers or
   5 libraries. However, they use the sys.prefix of the host Python, which
   6 returns incorrect paths when cross-compiling (paths pointing to host
   7 headers and libraries).
   8
   9 In order to fix this, we introduce the _python_sysroot, _python_prefix
  10 and _python_exec_prefix variables, that allow to override these
  11 values, and get correct header/library paths when cross-compiling
  12 third-party Python modules.
  13
  14 The _python_sysroot variable is also used to prefix the LIBDIR value
  15 taken from the sysconfigdata module.
  16
  17 Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
  18
  19 Index: b/Lib/distutils/sysconfig.py
  20 ===================================================================
  21 --- a/Lib/distutils/sysconfig.py
  22 +++ b/Lib/distutils/sysconfig.py
  23 @@ -19,8 +19,13 @@
  24  from distutils.errors import DistutilsPlatformError
  25
  26  # These are needed in a couple of spots, so just compute them once.
  27 -PREFIX = os.path.normpath(sys.prefix)
  28 -EXEC_PREFIX = os.path.normpath(sys.exec_prefix)
  29 +if "_python_sysroot" in os.environ:
  30 +    _sysroot=os.environ.get('_python_sysroot')
  31 +    PREFIX = os.path.normpath(_sysroot + os.environ.get('_python_prefix'))
  32 +    EXEC_PREFIX = os.path.normpath(_sysroot + os.environ.get('_python_exec_prefix'))
  33 +else:
  34 +    PREFIX = os.path.normpath(sys.prefix)
  35 +    EXEC_PREFIX = os.path.normpath(sys.exec_prefix)
  36
  37  # Path to the base directory of the project. On Windows the binary may
  38  # live in project/PCBuild9.  If we're dealing with an x64 Windows build,
  39 Index: b/Lib/distutils/command/build_ext.py
  40 ===================================================================
  41 --- a/Lib/distutils/command/build_ext.py
  42 +++ b/Lib/distutils/command/build_ext.py
  43 @@ -237,7 +237,10 @@
  44          if (sysconfig.get_config_var('Py_ENABLE_SHARED')):
  45              if not sysconfig.python_build:
  46                  # building third party extensions
  47 -                self.library_dirs.append(sysconfig.get_config_var('LIBDIR'))
  48 +                libdir = sysconfig.get_config_var('LIBDIR')
  49 +                if "_python_sysroot" in os.environ:
  50 +                    libdir = os.environ.get("_python_sysroot") + libdir
  51 +                self.library_dirs.append(libdir)
  52              else:
  53                  # building python standard extensions
  54                  self.library_dirs.append('.')