[gtk-osx] os.path.join won't work with empty values

[John Ralls <jralls src gnome org>]

commit 541a937b83777721ecaf9ec5e16171eb7a7888ee
Author: John Ralls <jralls ceridwen us>
Date:   Mon Feb 20 15:13:42 2012 -0800

    os.path.join won't work with empty values

 jhbuildrc-gtk-osx |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/jhbuildrc-gtk-osx b/jhbuildrc-gtk-osx
index 4ff15b3..3859b1d 100644
--- a/jhbuildrc-gtk-osx
+++ b/jhbuildrc-gtk-osx
@@ -174,8 +174,10 @@ def get_sdkdir(sdk_name):
     sdkpath = "Developer/SDKs"
     if _xcodeversion >= 4.3:
         platformpath = "Developer/Platforms/MacOSX.platform"
-
-    sdkdir = os.path.join(_xcodepath, platformpath, sdkpath, sdk_name)
+    if _xcodepath and platformpath:
+        sdkdir = os.path.join(_xcodepath, platformpath, sdkpath, sdk_name)
+    else:
+        sdkdir = os.path.join("/", sdkpath, sdk_name)
     return sdkdir
 #
 # This is the workhorse of the setup. Call this function with the