More block constification

I noticed that there are still many places referring to non-const
blocks.  This constifies all the remaining ones that I found that
could be constified.

In a few spots, this search found unused variables or fields.  I
removed these.  I've also removed some unnecessary casts to
"struct block *".

gdb/ChangeLog
2019-03-24  Tom Tromey  <tom@tromey.com>

	* c-exp.y (typebase): Remove casts.
	* gdbtypes.c (lookup_unsigned_typename, )
	(lookup_signed_typename): Remove cast.
	* eval.c (parse_to_comma_and_eval): Remove cast.
	* parse.c (write_dollar_variable): Remove cast.
	* block.h (struct block) <superblock>: Now const.
	* symfile-debug.c (debug_qf_map_matching_symbols): Update.
	* psymtab.c (psym_map_matching_symbols): Make "block" const.
	(map_block): Make "block" const.
	* symfile.h (struct quick_symbol_functions)
	<map_matching_symbols>: Constify block argument to "callback".
	* symtab.c (basic_lookup_transparent_type_quick): Make "block"
	const.
	(find_pc_sect_compunit_symtab): Make "b" const.
	(find_symbol_at_address): Likewise.
	(search_symbols): Likewise.
	* dwarf2read.c (dw2_lookup_symbol): Make "block" const.
	(dw2_debug_names_lookup_symbol): Likewise.
	(dw2_map_matching_symbols): Update.
	* p-valprint.c (pascal_val_print): Remove "block".
	* ada-lang.c (ada_add_global_exceptions): Make "b" const.
	(aux_add_nonlocal_symbols): Make "block" const.
	(resolve_subexp): Remove cast.
	* linespec.c (iterate_over_all_matching_symtabs): Make "block"
	const.
	(iterate_over_file_blocks): Likewise.
	* f-exp.y (%union) <bval>: Remove.
	* coffread.c (patch_opaque_types): Make "b" const.
	* spu-tdep.c (spu_catch_start): Make "block" const.
	* c-valprint.c (print_unpacked_pointer): Remove "block".
	* symmisc.c (dump_symtab_1): Make "b" const.
	(block_depth): Make "block" const.
	* d-exp.y (%union) <bval>: Remove.
	* cp-support.h (cp_lookup_rtti_type): Update.
	* cp-support.c (cp_lookup_rtti_type): Make "block" const.
	* psymtab.c (psym_lookup_symbol): Make "block" const.
	(maintenance_check_psymtabs): Make "b" const.
	* python/py-framefilter.c (extract_sym): Make "sym_block" const.
	(enumerate_locals, enumerate_args): Update.
	* python/py-symtab.c (stpy_global_block): Make "block" const.
	(stpy_static_block): Likewise.
	* inline-frame.c (block_starting_point_at): Make "new_block"
	const.
	* block.c (find_block_in_blockvector): Make return type const.
	(blockvector_for_pc_sect): Make "b" const.
	(find_block_in_blockvector): Make "b" const.

2 files changed, 5 insertions, 5 deletions

diff --git a/gdb/python/py-framefilter.c b/gdb/python/py-framefilter.c
index 7f416cb..7b241bb 100644
--- a/gdb/python/py-framefilter.c
+++ b/gdb/python/py-framefilter.c
@@ -54,7 +54,7 @@ enum mi_print_types
 
 static enum ext_lang_bt_status
 extract_sym (PyObject *obj, gdb::unique_xmalloc_ptr<char> *name,
-	     struct symbol **sym, struct block **sym_block,
+	     struct symbol **sym, const struct block **sym_block,
 	     const struct language_defn **language)
 {
   gdbpy_ref<> result (PyObject_CallMethod (obj, "symbol", NULL));
@@ -449,7 +449,7 @@ enumerate_args (PyObject *iter,
       const struct language_defn *language;
       gdb::unique_xmalloc_ptr<char> sym_name;
       struct symbol *sym;
-      struct block *sym_block;
+      const struct block *sym_block;
       struct value *val;
       enum ext_lang_bt_status success = EXT_LANG_BT_ERROR;
 
@@ -567,7 +567,7 @@ enumerate_locals (PyObject *iter,
       struct value *val;
       enum ext_lang_bt_status success = EXT_LANG_BT_ERROR;
       struct symbol *sym;
-      struct block *sym_block;
+      const struct block *sym_block;
       int local_indent = 8 + (8 * indent);
       gdb::optional<ui_out_emit_tuple> tuple;
 
diff --git a/gdb/python/py-symtab.c b/gdb/python/py-symtab.c
index 0fef6e4..15af300 100644
--- a/gdb/python/py-symtab.c
+++ b/gdb/python/py-symtab.c
@@ -176,7 +176,7 @@ static PyObject *
 stpy_global_block (PyObject *self, PyObject *args)
 {
   struct symtab *symtab = NULL;
-  struct block *block = NULL;
+  const struct block *block = NULL;
   const struct blockvector *blockvector;
 
   STPY_REQUIRE_VALID (self, symtab);
@@ -192,7 +192,7 @@ static PyObject *
 stpy_static_block (PyObject *self, PyObject *args)
 {
   struct symtab *symtab = NULL;
-  struct block *block = NULL;
+  const struct block *block = NULL;
   const struct blockvector *blockvector;
 
   STPY_REQUIRE_VALID (self, symtab);