/* lookup a symbol table by source file name */
-extern struct symtab *lookup_symtab (char *);
+extern struct symtab *lookup_symtab (const char *);
/* lookup a symbol by name (optional block, optional symtab) */
/* lookup partial symbol table by filename */
-extern struct partial_symtab *lookup_partial_symtab (char *);
+extern struct partial_symtab *lookup_partial_symtab (const char *);
/* lookup partial symbol table by address */