Fix compilation on platforms with unsgined char

diff --git a/src/script.c b/src/script.c
index 66a15a770ac1d0088b88cb7b0adad4842e539f9f..2117aebe1cd4201cdfdf632eb881d143715d07b6 100644 (file)
--- a/src/script.c
+++ b/src/script.c
@@ -24,7 +24,7 @@
 #include "odhcp6c.h"
 
 static const char hexdigits[] = "0123456789abcdef";
-static const char hexvals[] = {
+static const int8_t hexvals[] = {
     -1, -1, -1, -1, -1, -1, -1, -1, -1, -2, -2, -1, -1, -2, -1, -1,
     -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
     -2, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,