From 83d39ff9c96f33b413341fb0c56da24bfd850ff8 Mon Sep 17 00:00:00 2001
From: HuangWei <huangwei5@xiaomi.com>
Date: Sat, 13 Jun 2020 12:43:41 +0800
Subject: [PATCH] Avoid pass NULL to memcmp() (#3844)

If we exec "StringVal(len=0, ptr="") == StringVal(len=0,ptr=NULL)", it will pass NULL ptr to memcmp(). It should be avoided.
---
 be/src/udf/udf.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/be/src/udf/udf.h b/be/src/udf/udf.h
index 9013d20cfb..3ed500d7c9 100755
--- a/be/src/udf/udf.h
+++ b/be/src/udf/udf.h
@@ -644,7 +644,7 @@ struct StringVal : public AnyVal {
             return false;
         }
 
-        return ptr == other.ptr || memcmp(ptr, other.ptr, len) == 0;
+        return len == 0 || ptr == other.ptr || memcmp(ptr, other.ptr, len) == 0;
     }
 
     bool operator!=(const StringVal& other) const {