[Beignet] [PATCH 1/3] Use OCL_USE_PCH to control the using pch or not.

[Yang Rong]

Junyan has added the environment variable OCL_USE_PCH, but not using it.
Enable it.

Signed-off-by: Yang Rong <rong.r.yang at intel.com>
---
 backend/src/backend/program.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/backend/src/backend/program.cpp b/backend/src/backend/program.cpp
index 3ab1bc2..993905f 100644
--- a/backend/src/backend/program.cpp
+++ b/backend/src/backend/program.cpp
@@ -658,7 +658,7 @@ namespace gbe {
     FILE *clFile = fopen(clName.c_str(), "w");
     FATAL_IF(clFile == NULL, "Failed to open temporary file");
 
-    bool usePCH = true;
+    bool usePCH = OCL_USE_PCH;
     bool findPCH = false;
 
     /* Because our header file is so big, we want to avoid recompile the header from
-- 
1.8.3.2