[Python-checkins] bpo-41116: Ensure system supplied libraries are found on macOS 11 (GH-23301)

Sun Nov 22 00:14:31 EST 2020

https://github.com/python/cpython/commit/404a719b5127602c1a948f8e189ab61cd3f147d8
commit: 404a719b5127602c1a948f8e189ab61cd3f147d8
branch: master
author: Ronald Oussoren <ronaldoussoren at mac.com>
committer: ned-deily <nad at python.org>
date: 2020年11月22日T00:14:25-05:00
summary:
bpo-41116: Ensure system supplied libraries are found on macOS 11 (GH-23301)
On macOS system provided libraries are in a shared library cache
and not at their usual location. This PR teaches distutils to search
in the SDK, even if there was no "-sysroot" argument in
the compiler flags.
files:
A Misc/NEWS.d/next/macOS/2020-11-15-16-43-45.bpo-41116.oCkbrF.rst
M Lib/_osx_support.py
M Lib/distutils/unixccompiler.py
M setup.py

diff --git a/Lib/_osx_support.py b/Lib/_osx_support.py
index 0cbfeed0c4ecf..37975fe8a3eef 100644
--- a/Lib/_osx_support.py
+++ b/Lib/_osx_support.py
@@ -52,7 +52,7 @@ def _find_executable(executable, path=None):
 return executable
 
 
-def _read_output(commandstring):
+def _read_output(commandstring, capture_stderr=False):
 """Output from successful command execution or None"""
 # Similar to os.popen(commandstring, "r").read(),
 # but without actually using os.popen because that
@@ -67,7 +67,10 @@ def _read_output(commandstring):
 os.getpid(),), "w+b")
 
 with contextlib.closing(fp) as fp:
- cmd = "%s 2>/dev/null >'%s'" % (commandstring, fp.name)
+ if capture_stderr:
+ cmd = "%s >'%s' 2>&1" % (commandstring, fp.name)
+ else:
+ cmd = "%s 2>/dev/null >'%s'" % (commandstring, fp.name)
 return fp.read().decode('utf-8').strip() if not os.system(cmd) else None
 
 
@@ -145,6 +148,33 @@ def _save_modified_value(_config_vars, cv, newvalue):
 _config_vars[_INITPRE + cv] = oldvalue
 _config_vars[cv] = newvalue
 
+
+_cache_default_sysroot = None
+def _default_sysroot(cc):
+ """ Returns the root of the default SDK for this system, or '/' """
+ global _cache_default_sysroot
+
+ if _cache_default_sysroot is not None:
+ return _cache_default_sysroot
+ 
+ contents = _read_output('%s -c -E -v - </dev/null' % (cc,), True)
+ in_incdirs = False 
+ for line in contents.splitlines():
+ if line.startswith("#include <...>"):
+ in_incdirs = True
+ elif line.startswith("End of search list"):
+ in_incdirs = False
+ elif in_incdirs:
+ line = line.strip()
+ if line == '/usr/include':
+ _cache_default_sysroot = '/'
+ elif line.endswith(".sdk/usr/include"):
+ _cache_default_sysroot = line[:-12]
+ if _cache_default_sysroot is None:
+ _cache_default_sysroot = '/'
+
+ return _cache_default_sysroot
+
 def _supports_universal_builds():
 """Returns True if universal builds are supported on this system"""
 # As an approximation, we assume that if we are running on 10.4 or above,
diff --git a/Lib/distutils/unixccompiler.py b/Lib/distutils/unixccompiler.py
index 4d7a6de740ab3..f0792de74a1a4 100644
--- a/Lib/distutils/unixccompiler.py
+++ b/Lib/distutils/unixccompiler.py
@@ -290,7 +290,7 @@ def find_library_file(self, dirs, lib, debug=0):
 cflags = sysconfig.get_config_var('CFLAGS')
 m = re.search(r'-isysroot\s*(\S+)', cflags)
 if m is None:
- sysroot = '/'
+ sysroot = _osx_support._default_sysroot(sysconfig.get_config_var('CC'))
 else:
 sysroot = m.group(1)
 
diff --git a/Misc/NEWS.d/next/macOS/2020-11-15-16-43-45.bpo-41116.oCkbrF.rst b/Misc/NEWS.d/next/macOS/2020-11-15-16-43-45.bpo-41116.oCkbrF.rst
new file mode 100644
index 0000000000000..c982224e92d71
--- /dev/null
+++ b/Misc/NEWS.d/next/macOS/2020-11-15-16-43-45.bpo-41116.oCkbrF.rst
@@ -0,0 +1 @@
+Ensure distutils.unixxcompiler.find_library_file can find system provided libraries on macOS 11.
\ No newline at end of file
diff --git a/setup.py b/setup.py
index 6546544a99d0d..398d9251a6c41 100644
--- a/setup.py
+++ b/setup.py
@@ -9,6 +9,7 @@
 import sys
 import sysconfig
 from glob import glob, escape
+import _osx_support
 
 
 try:
@@ -176,34 +177,10 @@ def macosx_sdk_root():
 m = re.search(r'-isysroot\s*(\S+)', cflags)
 if m is not None:
 MACOS_SDK_ROOT = m.group(1)
- MACOS_SDK_SPECIFIED = MACOS_SDK_ROOT != '/'
 else:
- MACOS_SDK_ROOT = '/'
- MACOS_SDK_SPECIFIED = False
- cc = sysconfig.get_config_var('CC')
- tmpfile = '/tmp/setup_sdk_root.%d' % os.getpid()
- try:
- os.unlink(tmpfile)
- except:
- pass
- ret = run_command('%s -E -v - </dev/null 2>%s 1>/dev/null' % (cc, tmpfile))
- in_incdirs = False
- try:
- if ret == 0:
- with open(tmpfile) as fp:
- for line in fp.readlines():
- if line.startswith("#include <...>"):
- in_incdirs = True
- elif line.startswith("End of search list"):
- in_incdirs = False
- elif in_incdirs:
- line = line.strip()
- if line == '/usr/include':
- MACOS_SDK_ROOT = '/'
- elif line.endswith(".sdk/usr/include"):
- MACOS_SDK_ROOT = line[:-12]
- finally:
- os.unlink(tmpfile)
+ MACOS_SDK_ROOT = _osx_support._default_sysroot(
+ sysconfig.get_config_var('CC'))
+ MACOS_SDK_SPECIFIED = MACOS_SDK_ROOT != '/'
 
 return MACOS_SDK_ROOT
 
