constify struct block in some places

This makes some spots in gdb, particularly general_symbol_info, use a
"const struct block", then fixes the fallout.

The justification is that, ordinarily, blocks ought to be readonly.
Note though that we can't add "const" in the blockvector due to block
relocation.  This can be done once blocks are made independent of the
program space.

2014-06-18  Tom Tromey  <tromey@redhat.com>

	* varobj.c (varobj_create): Update.
	* valops.c (value_of_this): Update.
	* tracepoint.c (add_local_symbols, scope_info): Update.
	* symtab.h (struct general_symbol_info) <block>: Now const.
	* symtab.c (skip_prologue_sal)
	(default_make_symbol_completion_list_break_on)
	(skip_prologue_using_sal): Update.
	* stack.h (iterate_over_block_locals)
	(iterate_over_block_local_vars): Update.
	* stack.c (print_frame_args): Update.
	(iterate_over_block_locals, iterate_over_block_local_vars): Make
	parameter const.
	(get_selected_block): Make return type const.
	* python/py-frame.c (frapy_block): Update.
	* python/py-block.c (gdbpy_block_for_pc): Update.
	* p-exp.y (%union) <bval>: Now const.
	* mi/mi-cmd-stack.c (list_args_or_locals): Update.
	* mdebugread.c (mylookup_symbol, parse_procedure): Update.
	* m2-exp.y (%union) <bval>: Now const.
	* linespec.c (get_current_search_block): Make return type const.
	(create_sals_line_offset, find_label_symbols): Update.
	* inline-frame.c (inline_frame_sniffer, skip_inline_frames):
	Update.
	(block_starting_point_at): Make "block" const.
	* infrun.c (insert_exception_resume_breakpoint): Make "b" const.
	(check_exception_resume): Update.
	* guile/scm-frame.c (gdbscm_frame_block): Update.
	* guile/scm-block.c (gdbscm_lookup_block): Update.
	* frame.h (get_frame_block): Update.
	(get_selected_block): Make return type const.
	* frame.c (frame_id_inner): Update.
	* f-valprint.c (info_common_command_for_block)
	(info_common_command): Update.
	* dwarf2loc.c (dwarf2_find_location_expression)
	(dwarf_expr_frame_base, dwarf2_compile_expr_to_ax)
	(locexpr_describe_location_piece): Update.
	* c-exp.y (%union) <bval>: Now const.
	* breakpoint.c (resolve_sal_pc): Update.
	* blockframe.c (get_frame_block):Make return type const.
	(get_pc_function_start, get_frame_function, find_pc_sect_function)
	(block_innermost_frame): Update.
	* block.h (blockvector_for_pc, blockvector_for_pc_sect)
	(block_for_pc, block_for_pc_sect): Update.
	* block.c (blockvector_for_pc_sect, blockvector_for_pc): Make
	'pblock' const.
	(block_for_pc_sect, block_for_pc): Make return type const.
	* ax-gdb.c (gen_expr): Update.
	* alpha-mdebug-tdep.c (find_proc_desc): Update.
	* ada-lang.c (ada_read_renaming_var_value): Make 'block' const.
	(ada_make_symbol_completion_list, ada_add_exceptions_from_frame)
	(ada_read_var_value): Update.
	* ada-exp.y (struct name_info) <block>: Now const.
	(%union): Likewise.
	(block_lookup): Constify.

1 files changed, 4 insertions, 4 deletions

diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index 56b3708..fb627b7 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -4168,7 +4168,7 @@ parse_old_style_renaming (struct type *type,
 
 static struct value *
 ada_read_renaming_var_value (struct symbol *renaming_sym,
-			     struct block *block)
+			     const struct block *block)
 {
   const char *sym_name;
   struct expression *expr;
@@ -6133,7 +6133,7 @@ ada_make_symbol_completion_list (const char *text0, const char *word,
   struct symtab *s;
   struct minimal_symbol *msymbol;
   struct objfile *objfile;
-  struct block *b, *surrounding_static_block = 0;
+  const struct block *b, *surrounding_static_block = 0;
   int i;
   struct block_iterator iter;
   struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
@@ -12758,7 +12758,7 @@ static void
 ada_add_exceptions_from_frame (regex_t *preg, struct frame_info *frame,
 			       VEC(ada_exc_info) **exceptions)
 {
-  struct block *block = get_frame_block (frame, 0);
+  const struct block *block = get_frame_block (frame, 0);
 
   while (block != 0)
     {
@@ -13444,7 +13444,7 @@ ada_get_symbol_name_cmp (const char *lookup_name)
 static struct value *
 ada_read_var_value (struct symbol *var, struct frame_info *frame)
 {
-  struct block *frame_block = NULL;
+  const struct block *frame_block = NULL;
   struct symbol *renaming_sym = NULL;
 
   /* The only case where default_read_var_value is not sufficient