bpo-41282: Fix broken `make install` (GH-26329)
A previous commit broke a check in sysconfig when building cpython itself.
This caused builds of the standard library modules to search a wrong
location (the installed location rather than the source directory) for
header files with the net effect that a ``make install``
incorrectly caused all extension modules to be rebuilt again and
with incorrect include file paths.
When building Python, we need two distinct "include" directories:
- source .h files
- install target for .h files
Note that this doesn't matter except when building Python from source.
Historically:
- source .h files were in the distutils scheme under 'include'
- the install directory was in the distutils.command.install scheme
under 'headers'
GH-24549 merged these; sysconfig is now the single source of truth and
distutils is derived from it.
This commit introduces a "secret" scheme path, 'headers', which contains
the install target. It is only present when building Python.
The distutils code uses it if present, and falls back to 'include'.
Co-authored-by: Ned Deily <nad@python.org>
(cherry picked from commit 563bd5a4dcc6a26e47966cb66db64859902bce76)
Co-authored-by: Petr Viktorin <encukou@gmail.com>diff --git a/Lib/distutils/command/install.py b/Lib/distutils/command/install.py
index d33a889..26696cf 100644
--- a/Lib/distutils/command/install.py
+++ b/Lib/distutils/command/install.py
@@ -37,12 +37,19 @@
# Copy from sysconfig._INSTALL_SCHEMES
for key in SCHEME_KEYS:
- sys_key = key
- if key == "headers":
- sys_key = "include"
- INSTALL_SCHEMES["unix_prefix"][key] = sysconfig._INSTALL_SCHEMES["posix_prefix"][sys_key]
- INSTALL_SCHEMES["unix_home"][key] = sysconfig._INSTALL_SCHEMES["posix_home"][sys_key]
- INSTALL_SCHEMES["nt"][key] = sysconfig._INSTALL_SCHEMES["nt"][sys_key]
+ for distutils_scheme_name, sys_scheme_name in (
+ ("unix_prefix", "posix_prefix"), ("unix_home", "posix_home"),
+ ("nt", "nt")):
+ sys_key = key
+ sys_scheme = sysconfig._INSTALL_SCHEMES[sys_scheme_name]
+ if key == "headers" and key not in sys_scheme:
+ # On POSIX-y platofrms, Python will:
+ # - Build from .h files in 'headers' (only there when
+ # building CPython)
+ # - Install .h files to 'include'
+ # When 'headers' is missing, fall back to 'include'
+ sys_key = 'include'
+ INSTALL_SCHEMES[distutils_scheme_name][key] = sys_scheme[sys_key]
# Transformation to different template format
for main_key in INSTALL_SCHEMES:
@@ -316,6 +323,9 @@ def finalize_options(self):
self.config_vars['userbase'] = self.install_userbase
self.config_vars['usersite'] = self.install_usersite
+ if sysconfig.is_python_build(True):
+ self.config_vars['srcdir'] = sysconfig.get_config_var('srcdir')
+
self.expand_basedirs()
self.dump_dirs("post-expand_basedirs()")