diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 24c3e92..34af0d3 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -1154,13 +1154,8 @@
     return get_ipv6_addr(ipv6_prefix_spec, &t_addr, &t_bits, M_WARN);
 }
 
-#if defined(__GNUC__) || defined(__clang__)
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wconversion"
-#endif
-
 static char *
-string_substitute(const char *src, int from, int to, struct gc_arena *gc)
+string_substitute(const char *src, char from, char to, struct gc_arena *gc)
 {
     char *ret = (char *)gc_malloc(strlen(src) + 1, true, gc);
     char *dest = ret;
@@ -9306,10 +9301,6 @@
     gc_free(&gc);
 }
 
-#if defined(__GNUC__) || defined(__clang__)
-#pragma GCC diagnostic pop
-#endif
-
 bool
 has_udp_in_local_list(const struct options *options)
 {
diff --git a/src/openvpn/options.h b/src/openvpn/options.h
index 555d9dd..0561c25 100644
--- a/src/openvpn/options.h
+++ b/src/openvpn/options.h
@@ -801,7 +801,7 @@
 #define PUF_TYPE_IGNORE 2 /**< filter type to ignore a matching option */
 #define PUF_TYPE_REJECT 3 /**< filter type to reject and trigger SIGUSR1 */
     int type;
-    int size;
+    size_t size;
     char *pattern;
     struct pull_filter *next;
 };