naming abstraction
diff --git a/libasn1compiler/asn1c_save.c b/libasn1compiler/asn1c_save.c
index 76f312b..d43da4f 100644
--- a/libasn1compiler/asn1c_save.c
+++ b/libasn1compiler/asn1c_save.c
@@ -243,7 +243,7 @@
 	FILE *fp_c, *fp_h;
 	char *tmpname_c, *tmpname_h;
 	char *name_buf;
-	char *header_id;
+	const char *header_id;
 	const char *c_retained = "";
 	const char *h_retained = "";
 	char *filename;