diff --git a/src/intl/charsets.c b/src/intl/charsets.c
index d92d78f4..06bb2c37 100644
--- a/src/intl/charsets.c
+++ b/src/intl/charsets.c
@@ -1046,7 +1046,7 @@ get_translation_table(int from, int to)
 }
 
 static inline int
-xxstrcmp(char *s1, char *s2, int l2)
+xxstrcmp(const char *s1, const char *s2, int l2)
 {
 	while (l2) {
 		if (*s1 > *s2) return 1;
@@ -1091,8 +1091,8 @@ compare_entities(const void *key_, const void *element_)
 	struct string *key = (struct string *) key_;
 	struct entity *element = (struct entity *) element_;
 	int length = key->length;
-	char *first = key->source;
-	char *second = element->s;
+	const char *first = key->source;
+	const char *second = element->s;
 
 	return xxstrcmp(first, second, length);
 }
diff --git a/src/intl/entity.inc b/src/intl/entity.inc
index f19b047c..4119eef2 100644
--- a/src/intl/entity.inc
+++ b/src/intl/entity.inc
@@ -1,6 +1,6 @@
 /* Automatically generated by gen-ent */
 
-static const struct entity { char *s; unicode_val_T c; } entities [1002] = {
+static const struct entity { const char *s; unicode_val_T c; } entities [1002] = {
 	{ "AElig",     0x00C6 }, /* LATIN CAPITAL LETTER AE                        */
 	{ "Aacgr",     0x0386 }, /* GREEK CAPITAL LETTER ALPHA WITH TONOS          */
 	{ "Aacute",    0x00C1 }, /* LATIN CAPITAL LETTER A WITH ACUTE              */