[c++] Disambiguate ModuleKind flags

In modules, 'attached to global module' nearly always means 'not in
module purview'.  Also the implementation treats, 'in global module &&
in module purview' as meaning 'header unit'.  The ModuleKind flags
reflected that.  The 'nearly always' means there are cases that the
first condition is not invariant, and that of course invalidates the
second equivalence.

This disambiguates the ModuleKind flags to allow that 'not quite', and
separate out header-unitness from the GMF & purview flags combination.

1) Separate out named-module vs header-unit from the MODULE/GLOBAL flags.

2) Replace the MODULE/GLOBAL flags with PURVIEW & ATTACH flags.

3) Adjust the parser state handling.

Lays ground-work for language-declaration changes.

	gcc/cp/
	* cp-tree.h (enum module_kind_bits): Disambiguate purview,
	attach, named module vs header-unit.
	(global_purview_p, not_module_p): Delete.
	(named_module_p): New.
	(header_module_p, module_purview_p): Adjust.
	(module_attach_p, named_module_purview_p): New.
	* decl.cc (duplicate_decls): Adjust.
	* module.cc (declare_module, preprocessed_module): Adjust.
	* name-lookup.cc (init_global_partition): Adjust.
	(get_fixed_binding_slot, pushdecl): Adjust.
	* parser.cc (cp_parser_module_declaration): Adjust.
	(cp_parser_import_declaration, cp_parser_declaration): Adjust.

1 files changed, 13 insertions, 16 deletions

diff --git a/gcc/cp/module.cc b/gcc/cp/module.cc
index 6126316..bd4771b 100644
--- a/gcc/cp/module.cc
+++ b/gcc/cp/module.cc
@@ -18971,25 +18971,21 @@ declare_module (module_state *module, location_t from_loc, bool exporting_p,
   gcc_checking_assert (module->is_direct () && module->has_location ());
 
   /* Yer a module, 'arry.  */
-  module_kind &= ~MK_GLOBAL;
-  module_kind |= MK_MODULE;
+  module_kind = module->is_header () ? MK_HEADER : MK_NAMED | MK_ATTACH;
 
-  if (module->is_partition () || exporting_p)
-    {
-      gcc_checking_assert (module->get_flatname ());
-
-      if (module->is_partition ())
-	module_kind |= MK_PARTITION;
-
-      if (exporting_p)
-	{
-	  module->interface_p = true;
-	  module_kind |= MK_INTERFACE;
-	}
+  // Even in header units, we consider the decls to be purview
+  module_kind |= MK_PURVIEW;
 
-      if (module->is_header ())
-	module_kind |= MK_GLOBAL | MK_EXPORTING;
+  if (module->is_partition ())
+    module_kind |= MK_PARTITION;
+  if (exporting_p)
+    {
+      module->interface_p = true;
+      module_kind |= MK_INTERFACE;
+    }
 
+  if (module_has_cmi_p ())
+    {
       /* Copy the importing information we may have already done.  We
 	 do not need to separate out the imports that only happen in
 	 the GMF, inspite of what the literal wording of the std
@@ -19523,6 +19519,7 @@ preprocessed_module (cpp_reader *reader)
 	  if (module->is_module ())
 	    {
 	      declare_module (module, cpp_main_loc (reader), true, NULL, reader);
+	      module_kind |= MK_EXPORTING;
 	      break;
 	    }
 	}