From 0241b53c72e4ef39962007be1df8e09702c0c751 Mon Sep 17 00:00:00 2001
From: Rafael Espindola <rafael.espindola@gmail.com>
Date: Wed, 14 Jan 2015 00:39:56 +0000
Subject: [PATCH] Don't set LD_PRELOAD to ''. It doesn't work on OpenBSD.

Patch by Brad Smith.

llvm-svn: 225890
---
 utils/lit/lit/TestingConfig.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/utils/lit/lit/TestingConfig.py b/utils/lit/lit/TestingConfig.py
index 52cebbf6a41..c7ef94dc11f 100644
--- a/utils/lit/lit/TestingConfig.py
+++ b/utils/lit/lit/TestingConfig.py
@@ -26,7 +26,11 @@ class TestingConfig:
                      'LD_PRELOAD', 'ASAN_OPTIONS', 'UBSAN_OPTIONS',
                      'LSAN_OPTIONS']
         for var in pass_vars:
-            environment[var] = os.environ.get(var, '')
+            val = os.environ.get(var, '')
+            # Check for empty string as some variables such as LD_PRELOAD cannot be empty
+            # ('') for OS's such as OpenBSD.
+            if val:
+                environment[var] = val
 
         if sys.platform == 'win32':
             environment.update({