Record nested types

GDB currently does not track types defined in classes.  Consider:

class A
{
  public:

  class B
  {
    public:
      class C { };
  };
};

(gdb) ptype A
type = class A {
   <no data fields>
}

This patch changes this behavior so that GDB records these nested types
and displays them to the user when he has set the (new) "print type"
option "nested-type-limit."

Example:

(gdb) set print type nested-type-limit 1
(gdb) ptype A
type = class A {
    <no data fields>
    class A::B {
        <no data fields>
    };
}
(gdb) set print type nested-type-limit 2
type = class A {
    <no data fields>
    class A::B {
        <no data fields>
        class A::B::C {
            <no data fields>
        };
    };
}

By default, the code maintains the status quo, that is, it will not print
any nested type definitions at all.

Testing is carried out via cp_ptype_class which required quite a bit of
modification to permit recursive calling (for the nested types).  This
was most easily facilitated by turning the ptype command output into a
queue.  Upshot: the test suite now has stack and queue data structures that
may be used by test writers.

gdb/ChangeLog

	* NEWS (New commands): Mention set/show print type nested-type-limit.
	* c-typeprint.c (c_type_print_base): Print out nested types.
	* dwarf2read.c (struct typedef_field_list): Rename to ...
	(struct decl_field_list): ... this.  Change all uses.
	(struct field_info) <nested_types_list, nested_types_list_count>:
	New fields.
	(add_partial_symbol): Look for nested type definitions in C++, too.
	(dwarf2_add_typedef): Rename to ...
	(dwarf2_add_type_defn): ... this.
	(type_can_define_types): New function.
	Update assertion to use type_can_define_types.
	Permit NULL for a field's name.
	(process_structure_scope): Handle child DIEs of types that can
	define types.
	Copy the list of nested types into the type struct.
	* gdbtypes.h (struct typedef_field): Rename to ...
	(struct decl_field): ... this.  Change all uses.
	[is_protected, is_private]: New fields.
	(struct cplus_struct_type) <nested_types, nested_types_count>: New
	fields.
	(TYPE_NESTED_TYPES_ARRAY, TYPE_NESTED_TYPES_FIELD)
	(TYPE_NESTED_TYPES_FIELD_NAME, TYPE_NESTED_TYPES_FIELD_TYPE)
	(TYPE_NESTED_TYPES_COUNT, TYPE_NESTED_TYPES_FIELD_PROTECTED)
	(TYPE_NESTED_TYPES_FIELD_PRIVATE): New macros.
	* typeprint.c (type_print_raw_options, default_ptype_flags): Add
	default value for print_nested_type_limit.
	(print_nested_type_limit): New static variable.
	(set_print_type_nested_types, show_print_type_nested_types): New
	functions.
	(_initialize_typeprint): Register new commands for set/show
	`print-nested-type-limit'.
	* typeprint.h (struct type_print_options) [print_nested_type_limit]:
	New field.

gdb/testsuite/ChangeLog

	* gdb.cp/nested-types.cc: New file.
	* gdb.cp/nested-types.exp: New file.
	* lib/cp-support.exp: Load data-structures.exp library.
	(debug_cp_test_ptype_class): New global.
	(cp_ptype_class_verbose, next_line): New procedures.
	(cp_test_ptype_class): Add and document new parameter `recursive_qid'.
	Add and document new return value.
	Switch the list of lines to a queue.
	Add support for new `type' key for nested type definitions.
	Add debugging/troubleshooting messages.
	* lib/data-structures.exp: New file.

gdb/doc/ChangeLog

	* gdb.texinfo (Symbols): Document "set print type nested-type-limit"
	and "show print type nested-type-limit".

2 files changed, 18 insertions, 0 deletions

diff --git a/gdb/doc/ChangeLog b/gdb/doc/ChangeLog
index 419efc4..df294d6 100644
--- a/gdb/doc/ChangeLog
+++ b/gdb/doc/ChangeLog
@@ -1,3 +1,8 @@
+2017-12-07  Keith Seitz  <keiths@redhat.com>
+
+	* gdb.texinfo (Symbols): Document "set print type nested-type-limit"
+	and "show print type nested-type-limit".
+
 2017-12-07  Phil Muldoon  <pmuldoon@redhat.com>
 
        * python.texi (Breakpoints In Python): Add text relating
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 3b251c6..1e4ef98 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -17071,6 +17071,19 @@ cause @value{GDBN} to omit the methods.
 This command shows the current setting of method display when printing
 classes.
 
+@kindex set print type nested-type-limit
+@item set print type nested-type-limit @var{limit}
+@itemx set print type nested-type-limit unlimited
+Set the limit of displayed nested types that the type printer will
+show.  A @var{limit} of @code{unlimited} or @code{-1} will show all
+nested definitions.  By default, the type printer will not show any nested
+types defined in classes.
+
+@kindex show print type nested-type-limit
+@item show print type nested-type-limit
+This command shows the current display limit of nested types when
+printing classes.
+
 @kindex set print type typedefs
 @item set print type typedefs
 @itemx set print type typedefs on