diff --git a/llvm/utils/lit/lit/TestingConfig.py b/llvm/utils/lit/lit/TestingConfig.py
--- a/llvm/utils/lit/lit/TestingConfig.py
+++ b/llvm/utils/lit/lit/TestingConfig.py
@@ -33,6 +33,7 @@
             pass_vars.append('INCLUDE')
             pass_vars.append('LIB')
             pass_vars.append('PATHEXT')
+            pass_vars.append('USERPROFILE')
             environment['PYTHONBUFFERED'] = '1'
 
         for var in pass_vars: