$OpenBSD$

index ed82400..d00d987 100644
--- python/mozbuild/mozbuild/base.py.orig	Fri Feb 20 15:40:38 2015
+++ python/mozbuild/mozbuild/base.py	Fri Feb 20 15:40:38 2015
@@ -457,7 +457,7 @@ class MozbuildObject(ProcessExecutionMixin):
             'append_env': append_env,
             'explicit_env': explicit_env,
             'log_level': logging.INFO,
-            'require_unix_environment': True,
+            'require_unix_environment': False,
             'ensure_exit_code': ensure_exit_code,
             'pass_thru': pass_thru,
 
@@ -554,6 +554,15 @@ class MachCommandBase(MozbuildObject):
             topobjdir = dummy._topobjdir
         except BuildEnvironmentNotFoundException:
             pass
+        except ObjdirMismatchException as e:
+            print('Ambiguous object directory detected. We detected that '
+                'both %s and %s could be object directories. This is '
+                'typically caused by having a mozconfig pointing to a '
+                'different object directory from the current working '
+                'directory. To solve this problem, ensure you do not have a '
+                'default mozconfig in searched paths.' % (e.objdir1,
+                    e.objdir2))
+            sys.exit(1)
 
         MozbuildObject.__init__(self, topsrcdir, context.settings,
             context.log_manager, topobjdir=topobjdir)