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, 5 insertions, 5 deletions

diff --git a/gdb/ada-exp.y b/gdb/ada-exp.y
index 9815f23..96188ac 100644
--- a/gdb/ada-exp.y
+++ b/gdb/ada-exp.y
@@ -110,7 +110,7 @@
 struct name_info {
   struct symbol *sym;
   struct minimal_symbol *msym;
-  struct block *block;
+  const struct block *block;
   struct stoken stoken;
 };
 
@@ -145,7 +145,7 @@ static void write_name_assoc (struct parser_state *, struct stoken);
 static void write_exp_op_with_string (struct parser_state *, enum exp_opcode,
 				      struct stoken);
 
-static struct block *block_lookup (struct block *, const char *);
+static const struct block *block_lookup (const struct block *, const char *);
 
 static LONGEST convert_char_literal (struct type *, LONGEST);
 
@@ -185,7 +185,7 @@ static struct type *type_system_address (struct parser_state *);
     } typed_val_float;
     struct type *tval;
     struct stoken sval;
-    struct block *bval;
+    const struct block *bval;
     struct internalvar *ivar;
   }
 
@@ -1010,8 +1010,8 @@ write_object_renaming (struct parser_state *par_state,
   error (_("Internal error in encoding of renaming declaration"));
 }
 
-static struct block*
-block_lookup (struct block *context, const char *raw_name)
+static const struct block*
+block_lookup (const struct block *context, const char *raw_name)
 {
   const char *name;
   struct ada_symbol_info *syms;