implement support for "enum class"

This adds support for the C++11 "enum class" feature.  This is
PR c++/15246.

I chose to use the existing TYPE_DECLARED_CLASS rather than introduce
a new type code.  This seemed both simple and clear to me.

I made overloading support for the new enum types strict.  This is how
it works in C++; and it didn't seem like an undue burden to keep this,
particularly because enum constants are printed symbolically by gdb.

Built and regtested on x86-64 Fedora 20.

2014-04-14  Tom Tromey  <tromey@redhat.com>

	PR c++/15246:
	* c-exp.y (type_aggregate_p): New function.
	(qualified_name, classify_inner_name): Use it.
	* c-typeprint.c (c_type_print_base): Handle TYPE_DECLARED_CLASS
	and TYPE_TARGET_TYPE of an enum type.
	* dwarf2read.c (read_enumeration_type): Set TYPE_DECLARED_CLASS on
	an enum type.
	(determine_prefix) <case DW_TAG_enumeration_type>: New case;
	handle TYPE_DECLARED_CLASS.
	* gdbtypes.c (rank_one_type): Handle TYPE_DECLARED_CLASS on enum
	types.
	* gdbtypes.h (TYPE_DECLARED_CLASS): Update comment.
	* valops.c (enum_constant_from_type): New function.
	(value_aggregate_elt): Use it.
	* cp-namespace.c (cp_lookup_nested_symbol): Handle
	TYPE_CODE_ENUM.

2014-04-14  Tom Tromey  <tromey@redhat.com>

	* gdb.cp/classes.exp (test_enums): Handle underlying type.
	* gdb.dwarf2/enum-type.exp: Add test for enum with underlying
	type.
	* gdb.cp/enum-class.exp: New file.
	* gdb.cp/enum-class.cc: New file.

1 files changed, 19 insertions, 0 deletions

diff --git a/gdb/c-typeprint.c b/gdb/c-typeprint.c
index d91005850c..305f92d588 100644
--- a/gdb/c-typeprint.c
+++ b/gdb/c-typeprint.c
@@ -1328,6 +1328,8 @@ c_type_print_base (struct type *type, struct ui_file *stream,
     case TYPE_CODE_ENUM:
       c_type_print_modifier (type, stream, 0, 1);
       fprintf_filtered (stream, "enum ");
+      if (TYPE_DECLARED_CLASS (type))
+	fprintf_filtered (stream, "class ");
       /* Print the tag name if it exists.
          The aCC compiler emits a spurious 
          "{unnamed struct}"/"{unnamed union}"/"{unnamed enum}"
@@ -1353,6 +1355,23 @@ c_type_print_base (struct type *type, struct ui_file *stream,
 	{
 	  LONGEST lastval = 0;
 
+	  /* We can't handle this case perfectly, as DWARF does not
+	     tell us whether or not the underlying type was specified
+	     in the source (and other debug formats don't provide this
+	     at all).  We choose to print the underlying type, if it
+	     has a name, when in C++ on the theory that it's better to
+	     print too much than too little; but conversely not to
+	     print something egregiously outside the current
+	     language's syntax.  */
+	  if (current_language->la_language == language_cplus
+	      && TYPE_TARGET_TYPE (type) != NULL)
+	    {
+	      struct type *underlying = check_typedef (TYPE_TARGET_TYPE (type));
+
+	      if (TYPE_NAME (underlying) != NULL)
+		fprintf_filtered (stream, ": %s ", TYPE_NAME (underlying));
+	    }
+
 	  fprintf_filtered (stream, "{");
 	  len = TYPE_NFIELDS (type);
 	  for (i = 0; i < len; i++)