diff --git a/utils/jz4740_tools/HXFmerge.c b/utils/jz4740_tools/HXFmerge.c
index 40c36e7bc7..f90d094fd9 100755
--- a/utils/jz4740_tools/HXFmerge.c
+++ b/utils/jz4740_tools/HXFmerge.c
@@ -193,10 +193,10 @@ static void print_usage(void)
 #endif
 }
 
-static unsigned int checksum(FILE *file)
+static int checksum(FILE *file)
 {
     int oldpos = ftell(file);
-    unsigned int ret, i, filesize = _filesize(file)-0x40;
+    int ret=0, i, filesize = _filesize(file)-0x40;
     unsigned char *buf;
     
     buf = (unsigned char*)malloc(filesize);
diff --git a/utils/jz4740_tools/HXFreplace.c b/utils/jz4740_tools/HXFreplace.c
index a33a729a1c..fc97a3c1e8 100755
--- a/utils/jz4740_tools/HXFreplace.c
+++ b/utils/jz4740_tools/HXFreplace.c
@@ -52,10 +52,10 @@ static void print_usage(void)
 #endif
 }
 
-static unsigned int checksum(FILE *file)
+static int checksum(FILE *file)
 {
     int oldpos = ftell(file);
-    unsigned int ret, i, filesize = _filesize(file)-0x40;
+    int ret=0, i, filesize = _filesize(file)-0x40;
     unsigned char *buf;
     
     buf = (unsigned char*)malloc(filesize);