[D] Support looking up symbols in the current and imported modules.

In D, there is the notion of modules, and importing from one to the other,
whether it is a basic, selective or renamed import declaration.

	module A;
	import X;
	void foo() {
	  import Y : bar;
	}

If the compiler emits DW_TAG_imported_declaration at the appropriate locations,
then we can make use of what gdb stores in using_direct when performing
nonlocal symbol lookups.

gdb/ChangeLog

	* Makefile.in (SFILES): Add d-namespace.c.
	(COMMON_OBS): Add d-namespace.o.
	* d-lang.c (d_language_defn): Use d_lookup_symbol_nonlocal as the
	la_lookup_symbol_nonlocal callback function pointer.
	* d-lang.h (d_lookup_symbol_nonlocal): New declaration.
	(d_lookup_nested_symbol): New declaration.
	* d-namespace.c: New file.

1 files changed, 10 insertions, 0 deletions

diff --git a/gdb/d-lang.h b/gdb/d-lang.h
index 4962a8a..8b8b5dc 100644
--- a/gdb/d-lang.h
+++ b/gdb/d-lang.h
@@ -68,6 +68,16 @@ extern char *d_demangle (const char *mangled, int options);
 
 extern const struct builtin_d_type *builtin_d_type (struct gdbarch *);
 
+/* Defined in d-namespace.c  */
+
+extern struct block_symbol d_lookup_symbol_nonlocal (const struct language_defn *,
+						     const char *,
+						     const struct block *,
+						     const domain_enum);
+
+extern struct block_symbol d_lookup_nested_symbol (struct type *, const char *,
+						   const struct block *);
+
 /* Defined in d-valprint.c  */
 
 extern void d_val_print (struct type *type, const gdb_byte *valaddr,