enforsed compilation with -W -Werror

diff --git a/libasn1compiler/asn1c_misc.c b/libasn1compiler/asn1c_misc.c
index b464b64..257e02c 100644
--- a/libasn1compiler/asn1c_misc.c
+++ b/libasn1compiler/asn1c_misc.c
@@ -94,6 +94,8 @@
 	FILE *fp;
 	int fd;
 
+	(void)arg;	/* Unused argument */
+
 	/*
 	 * Compute filenames.
 	 */
diff --git a/libasn1compiler/asn1c_save.c b/libasn1compiler/asn1c_save.c
index 8aab8c4..5e425d6 100644
--- a/libasn1compiler/asn1c_save.c
+++ b/libasn1compiler/asn1c_save.c
@@ -208,6 +208,8 @@
 asn1c_copy_over(arg_t *arg, char *path) {
 	char *fname = basename(path);
 
+	(void)arg;	/* Unused argument */
+
 	if(symlink(path, fname)) {
 		if(errno == EEXIST) {
 			struct stat sb1, sb2;
diff --git a/libasn1compiler/asn1compiler.c b/libasn1compiler/asn1compiler.c
index d647c05..24e539a 100644
--- a/libasn1compiler/asn1compiler.c
+++ b/libasn1compiler/asn1compiler.c
@@ -65,9 +65,9 @@
 	int (*type_cb)(arg_t *);
 	int ret;
 
-	assert(expr->meta_type >= AMT_INVALID);
+	assert((int)expr->meta_type >= AMT_INVALID);
 	assert(expr->meta_type < AMT_EXPR_META_MAX);
-	assert(expr->expr_type >= A1TC_INVALID);
+	assert((int)expr->expr_type >= A1TC_INVALID);
 	assert(expr->expr_type < ASN_EXPR_TYPE_MAX);
 
 	type_cb = asn1_lang_map[expr->meta_type][expr->expr_type].type_cb;