diff --git a/Source/cmGlobalXCodeGenerator.cxx b/Source/cmGlobalXCodeGenerator.cxx
index 59ca38f..6920756 100644
--- a/Source/cmGlobalXCodeGenerator.cxx
+++ b/Source/cmGlobalXCodeGenerator.cxx
@@ -2682,7 +2682,7 @@ void cmGlobalXCodeGenerator
       this->CreateObject(cmXCodeObject::ATTRIBUTE_GROUP);
   const char* osxArch =
       this->CurrentMakefile->GetDefinition("CMAKE_OSX_ARCHITECTURES");
-  if(strlen(osxArch) == 0)
+  if(!osxArch || strlen(osxArch) == 0)
     {
     if(this->XcodeVersion >= 32)
       {