bpo-38360: macOS: support alternate form of -isysroot flag (GH-16480)

It is possible to use either '-isysroot /some/path' (with a space) or
'-isysroot/some/path' (no space in between). Support both forms in
places where special handling of -isysroot is done, rather than just
the first form.
Co-authored-by: Ned Deily <nad@python.org>
(cherry picked from commit b310700976)

Co-authored-by: Joshua Root <jmr@macports.org>

Lib/_osx_support.py

@@ -211,7 +211,7 @@ def _remove_universal_flags(_config_vars):
         if cv in _config_vars and cv not in os.environ:
             flags = _config_vars[cv]
             flags = re.sub(r'-arch\s+\w+\s', ' ', flags, flags=re.ASCII)
-            flags = re.sub('-isysroot [^ \t]*', ' ', flags)
+            flags = re.sub(r'-isysroot\s*\S+', ' ', flags)
             _save_modified_value(_config_vars, cv, flags)
 
     return _config_vars
@@ -287,7 +287,7 @@ def _check_for_unavailable_sdk(_config_vars):
     # to /usr and /System/Library by either a standalone CLT
     # package or the CLT component within Xcode.
     cflags = _config_vars.get('CFLAGS', '')
-    m = re.search(r'-isysroot\s+(\S+)', cflags)
+    m = re.search(r'-isysroot\s*(\S+)', cflags)
     if m is not None:
         sdk = m.group(1)
         if not os.path.exists(sdk):
@@ -295,7 +295,7 @@ def _check_for_unavailable_sdk(_config_vars):
                 # Do not alter a config var explicitly overridden by env var
                 if cv in _config_vars and cv not in os.environ:
                     flags = _config_vars[cv]
-                    flags = re.sub(r'-isysroot\s+\S+(?:\s|$)', ' ', flags)
+                    flags = re.sub(r'-isysroot\s*\S+(?:\s|$)', ' ', flags)
                     _save_modified_value(_config_vars, cv, flags)
 
     return _config_vars
@@ -320,7 +320,7 @@ def compiler_fixup(compiler_so, cc_args):
         stripArch = stripSysroot = True
     else:
         stripArch = '-arch' in cc_args
-        stripSysroot = '-isysroot' in cc_args
+        stripSysroot = any(arg for arg in cc_args if arg.startswith('-isysroot'))
 
     if stripArch or 'ARCHFLAGS' in os.environ:
         while True:
@@ -338,23 +338,34 @@ def compiler_fixup(compiler_so, cc_args):
 
     if stripSysroot:
         while True:
-            try:
-                index = compiler_so.index('-isysroot')
+            indices = [i for i,x in enumerate(compiler_so) if x.startswith('-isysroot')]
+            if not indices:
+                break
+            index = indices[0]
+            if compiler_so[index] == '-isysroot':
                 # Strip this argument and the next one:
                 del compiler_so[index:index+2]
-            except ValueError:
-                break
+            else:
+                # It's '-isysroot/some/path' in one arg
+                del compiler_so[index:index+1]
 
     # Check if the SDK that is used during compilation actually exists,
     # the universal build requires the usage of a universal SDK and not all
     # users have that installed by default.
     sysroot = None
-    if '-isysroot' in cc_args:
-        idx = cc_args.index('-isysroot')
-        sysroot = cc_args[idx+1]
-    elif '-isysroot' in compiler_so:
-        idx = compiler_so.index('-isysroot')
-        sysroot = compiler_so[idx+1]
+    argvar = cc_args
+    indices = [i for i,x in enumerate(cc_args) if x.startswith('-isysroot')]
+    if not indices:
+        argvar = compiler_so
+        indices = [i for i,x in enumerate(compiler_so) if x.startswith('-isysroot')]
+
+    for idx in indices:
+        if argvar[idx] == '-isysroot':
+            sysroot = argvar[idx+1]
+            break
+        else:
+            sysroot = argvar[idx][len('-isysroot'):]
+            break
 
     if sysroot and not os.path.isdir(sysroot):
         from distutils import log

Lib/distutils/unixccompiler.py

@@ -288,7 +288,7 @@ class UnixCCompiler(CCompiler):
             # vs
             #   /usr/lib/libedit.dylib
             cflags = sysconfig.get_config_var('CFLAGS')
-            m = re.search(r'-isysroot\s+(\S+)', cflags)
+            m = re.search(r'-isysroot\s*(\S+)', cflags)
             if m is None:
                 sysroot = '/'
             else:

Lib/test/test__osx_support.py

@@ -174,6 +174,29 @@ class Test_OSXSupport(unittest.TestCase):
                             _osx_support._remove_universal_flags(
                                     config_vars))
 
+    def test__remove_universal_flags_alternate(self):
+        # bpo-38360: also test the alternate single-argument form of -isysroot
+        config_vars = {
+        'CFLAGS': '-fno-strict-aliasing  -g -O3 -arch ppc -arch i386  ',
+        'LDFLAGS': '-arch ppc -arch i386   -g',
+        'CPPFLAGS': '-I. -isysroot/Developer/SDKs/MacOSX10.4u.sdk',
+        'BLDSHARED': 'gcc-4.0 -bundle  -arch ppc -arch i386 -g',
+        'LDSHARED': 'gcc-4.0 -bundle  -arch ppc -arch i386 '
+                        '-isysroot/Developer/SDKs/MacOSX10.4u.sdk -g',
+        }
+        expected_vars = {
+        'CFLAGS': '-fno-strict-aliasing  -g -O3    ',
+        'LDFLAGS': '    -g',
+        'CPPFLAGS': '-I.  ',
+        'BLDSHARED': 'gcc-4.0 -bundle    -g',
+        'LDSHARED': 'gcc-4.0 -bundle      -g',
+        }
+        self.add_expected_saved_initial_values(config_vars, expected_vars)
+
+        self.assertEqual(expected_vars,
+                            _osx_support._remove_universal_flags(
+                                    config_vars))
+
     def test__remove_unsupported_archs(self):
         config_vars = {
         'CC': 'clang',
@@ -261,6 +284,34 @@ class Test_OSXSupport(unittest.TestCase):
                             _osx_support._check_for_unavailable_sdk(
                                     config_vars))
 
+    def test__check_for_unavailable_sdk_alternate(self):
+        # bpo-38360: also test the alternate single-argument form of -isysroot
+        config_vars = {
+        'CC': 'clang',
+        'CFLAGS': '-fno-strict-aliasing  -g -O3 -arch ppc -arch i386  '
+                        '-isysroot/Developer/SDKs/MacOSX10.1.sdk',
+        'LDFLAGS': '-arch ppc -arch i386   -g',
+        'CPPFLAGS': '-I. -isysroot/Developer/SDKs/MacOSX10.1.sdk',
+        'BLDSHARED': 'gcc-4.0 -bundle  -arch ppc -arch i386 -g',
+        'LDSHARED': 'gcc-4.0 -bundle  -arch ppc -arch i386 '
+                        '-isysroot/Developer/SDKs/MacOSX10.1.sdk -g',
+        }
+        expected_vars = {
+        'CC': 'clang',
+        'CFLAGS': '-fno-strict-aliasing  -g -O3 -arch ppc -arch i386  '
+                        ' ',
+        'LDFLAGS': '-arch ppc -arch i386   -g',
+        'CPPFLAGS': '-I.  ',
+        'BLDSHARED': 'gcc-4.0 -bundle  -arch ppc -arch i386 -g',
+        'LDSHARED': 'gcc-4.0 -bundle  -arch ppc -arch i386 '
+                        ' -g',
+        }
+        self.add_expected_saved_initial_values(config_vars, expected_vars)
+
+        self.assertEqual(expected_vars,
+                            _osx_support._check_for_unavailable_sdk(
+                                    config_vars))
+
     def test_get_platform_osx(self):
         # Note, get_platform_osx is currently tested more extensively
         # indirectly by test_sysconfig and test_distutils

Misc/NEWS.d/next/Build/2020-04-22-02-33-54.bpo-38360.74C68u.rst

@@ -0,0 +1 @@
+Support single-argument form of macOS -isysroot flag.

setup.py

@@ -110,7 +110,7 @@ def macosx_sdk_root():
         return MACOS_SDK_ROOT
 
     cflags = sysconfig.get_config_var('CFLAGS')
-    m = re.search(r'-isysroot\s+(\S+)', cflags)
+    m = re.search(r'-isysroot\s*(\S+)', cflags)
     if m is not None:
         MACOS_SDK_ROOT = m.group(1)
     else: