--- Lib/_osx_support.py.orig	2019-12-19 06:26:36.000000000 +1100
+++ Lib/_osx_support.py	2019-12-21 21:40:37.000000000 +1100
@@ -211,7 +211,7 @@
         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 @@
     # 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 @@
                 # 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 @@
         stripArch = stripSysroot = True
     else:
         stripArch = '-arch' in cc_args
-        stripSysroot = '-isysroot' in cc_args
+        stripSysroot = any(arg for arg in cc_args if arg.find('-isysroot') == 0)
 
     if stripArch or 'ARCHFLAGS' in os.environ:
         while True:
@@ -338,23 +338,34 @@
 
     if stripSysroot:
         while True:
-            try:
-                index = compiler_so.index('-isysroot')
+            indices = [i for i,x in enumerate(compiler_so) if x.find('-isysroot') == 0]
+            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.find('-isysroot') == 0]
+    if not indices:
+        argvar = compiler_so
+        indices = [i for i,x in enumerate(compiler_so) if x.find('-isysroot') == 0]
+
+    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.orig	2019-12-19 06:26:36.000000000 +1100
+++ Lib/distutils/unixccompiler.py	2019-12-21 21:39:17.000000000 +1100
@@ -282,7 +282,7 @@
             # 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:
--- setup.py.orig	2019-12-21 21:36:50.000000000 +1100
+++ setup.py	2019-12-21 21:38:02.000000000 +1100
@@ -96,7 +96,7 @@
     or '/' if no SDK was specified.
     """
     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: