libiberty/hashtab: More const parameters

Makes some parameters const in libiberty's hashtab library.

include/ChangeLog:

        * hashtab.h (htab_remove_elt): Make a parameter const.
        (htab_remove_elt_with_hash): Likewise.

libiberty/ChangeLog:

        * hashtab.c (htab_remove_elt): Make a parameter const.
        (htab_remove_elt_with_hash): Likewise.

include/ChangeLog

+2020-02-05  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* hashtab.h (htab_remove_elt): Make a parameter const.
+	(htab_remove_elt_with_hash): Likewise.
+
 2020-01-10  Thomas Schwinge  <thomas@codesourcery.com>
 
 	* gomp-constants.h (enum gomp_device_property): Remove.

include/hashtab.h

@@ -173,8 +173,8 @@ extern void *	htab_find_with_hash (htab_t, const void *, hashval_t);
 extern void **	htab_find_slot_with_hash (htab_t, const void *,
 					  hashval_t, enum insert_option);
 extern void	htab_clear_slot	(htab_t, void **);
-extern void	htab_remove_elt	(htab_t, void *);
-extern void	htab_remove_elt_with_hash (htab_t, void *, hashval_t);
+extern void	htab_remove_elt	(htab_t, const void *);
+extern void	htab_remove_elt_with_hash (htab_t, const void *, hashval_t);
 
 extern void	htab_traverse (htab_t, htab_trav, void *);
 extern void	htab_traverse_noresize (htab_t, htab_trav, void *);

libiberty/ChangeLog

+2020-02-05  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* hashtab.c (htab_remove_elt): Make a parameter const.
+	(htab_remove_elt_with_hash): Likewise.
+
 2020-01-23  Alexandre Oliva <oliva@adacore.com>
 
 	* argv.c (writeargv): Output empty args as "".

libiberty/hashtab.c

@@ -709,7 +709,7 @@ htab_find_slot (htab_t htab, const PTR element, enum insert_option insert)
    element in the hash table, this function does nothing.  */
 
 void
-htab_remove_elt (htab_t htab, PTR element)
+htab_remove_elt (htab_t htab, const PTR element)
 {
   htab_remove_elt_with_hash (htab, element, (*htab->hash_f) (element));
 }
@@ -720,7 +720,7 @@ htab_remove_elt (htab_t htab, PTR element)
    function does nothing.  */
 
 void
-htab_remove_elt_with_hash (htab_t htab, PTR element, hashval_t hash)
+htab_remove_elt_with_hash (htab_t htab, const PTR element, hashval_t hash)
 {
   PTR *slot;