value_maybe_namespace_elt: Remove redundant call to lookup_static_symbol.

Anytime you can remove a symbol lookup that loops over all objfiles
is A Good Thing.

The call to lookup_static_symbol in valops.c:value_maybe_namespace_elt
is redundant with this call in cp_lookup_nested_symbol:

	/* Now search all static file-level symbols.  We have to do this
	   for things like typedefs in the class.  We do not try to
	   guess any imported namespace as even the fully specified
	   namespace search is already not C++ compliant and more
	   assumptions could make it too magic.  */

	size = strlen (parent_name) + 2 + strlen (nested_name) + 1;
	concatenated_name = alloca (size);
	xsnprintf (concatenated_name, size, "%s::%s",
		 parent_name, nested_name);
	sym = lookup_static_symbol (concatenated_name, VAR_DOMAIN);
	if (sym != NULL)
	  return sym;

Earlier in value_maybe_namespace_elt we do this:

  sym = cp_lookup_symbol_namespace (namespace_name, name,
				    get_selected_block (0), VAR_DOMAIN);

That sequence goes like:

value_maybe_namespace_elt
-> cp_lookup_symbol_namespace
-> cp_lookup_symbol_in_namespace
-> lookup_symbol_file
-> cp_lookup_nested_symbol
-> lookup_static_symbol

The call was added in commit 41f62f3939b1c69e68ef5652feb44fef90eb85c9.
https://sourceware.org/ml/gdb-patches/2010-06/msg00663.html
With a part 2 here:
https://sourceware.org/ml/gdb-patches/2010-06/msg00664.html

At the time the call to lookup_static_symbol (spelled
lookup_static_symbol_aux at the time) was needed.

However, this patch, 8dea366bbed7986295681c101dcfbd35aeb6dfc4,
https://sourceware.org/ml/gdb-patches/2012-11/msg00387.html
augmented lookup_symbol_file to call cp_lookup_nested_symbol
and introduced the redundancy.

It's kinda buried, so it's totally not unexpected that this happened.

gdb/ChangeLog:

	* valops.c (value_maybe_namespace_elt): Remove redundant call to
	lookup_static_symbol.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 5704d43..b672dc3 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,10 @@
 2014-12-17  Doug Evans  <xdje42@gmail.com>
 
+       * valops.c (value_maybe_namespace_elt): Remove redundant call to
+       lookup_static_symbol.
+
+2014-12-17  Doug Evans  <xdje42@gmail.com>
+
        New parameter "debug symbol-lookup".
        * NEWS: Mention it.
        * cp-namespace.c (cp_lookup_symbol_imports_or_template): Add debug

diff --git a/gdb/valops.c b/gdb/valops.c
index 4d3059e..2f81a59 100644 (file)
--- a/gdb/valops.c
+++ b/gdb/valops.c
@@ -3570,15 +3570,6 @@ value_maybe_namespace_elt (const struct type *curtype,
                                    get_selected_block (0), VAR_DOMAIN);
 
   if (sym == NULL)
-    {
-      char *concatenated_name = alloca (strlen (namespace_name) + 2
-                                       + strlen (name) + 1);
-
-      sprintf (concatenated_name, "%s::%s", namespace_name, name);
-      sym = lookup_static_symbol (concatenated_name, VAR_DOMAIN);
-    }
-
-  if (sym == NULL)
     return NULL;
   else if ((noside == EVAL_AVOID_SIDE_EFFECTS)
           && (SYMBOL_CLASS (sym) == LOC_TYPEDEF))