Backport of r52236

diff --git a/Lib/distutils/unixccompiler.py b/Lib/distutils/unixccompiler.py
index 6cd14f77288a7b646904d7a4a48f9f9e466da118..d1fd1d95112ac023aad7badaf874a3745ef02a62 100644 (file)
--- a/Lib/distutils/unixccompiler.py
+++ b/Lib/distutils/unixccompiler.py
@@ -82,6 +82,22 @@ def _darwin_compiler_fixup(compiler_so, cc_args):
         except ValueError:
             pass
 
+    # 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]
+
+    if sysroot and not os.path.isdir(sysroot):
+        log.warn("Compiling with an SDK that doesn't seem to exist: %s",
+                sysroot)
+        log.warn("Please check your Xcode installation")
+
     return compiler_so
 
 class UnixCCompiler(CCompiler):