Re: [patch 2/2] Perform a namespace lookup at every block level

[Sami Wagiaalla <swagiaal at redhat dot com>]

Updating patch because of changes in patch 1/2



2009-11-16  Sami Wagiaalla  <swagiaal@redhat.com>
      * cp-namespace.c (cp_lookup_symbol_namespace): Added
      search_parent argument.
      (cp_add_using): Initialize 'searched' field.
      (cp_copy_usings): Copy searched field.
      * cp-support.h: Add 'searched' field to using_direct struct.
      (cp_lookup_symbol_imports): Ditto.
      * cp-namespace.c (cp_lookup_symbol_imports): Ditto.
      Perform recursive search.
      Implement non parent search.
      * valops.c (value_maybe_namespace_elt): Updated.

2009-11-16  Sami Wagiaalla  <swagiaal@redhat.com>
      * gdb.cp/namespace-stress.exp: New test.
      * gdb.cp/namespace-stress.cc: New test program.
      * gdb.cp/namespace-recursive.exp: New test.
      * gdb.cp/namespace-recursive.cc: New test program.
      * gdb.cp/namespace-stress.exp: New test.
      * gdb.cp/namespace-stress.cc: New test program.

diff --git a/gdb/cp-namespace.c b/gdb/cp-namespace.c
index f63cf8a..e2f1d43 100644
--- a/gdb/cp-namespace.c
+++ b/gdb/cp-namespace.c
@@ -217,6 +217,7 @@ cp_add_using (const char *dest,
   retval->import_src = savestring (src, strlen(src));
   retval->import_dest = savestring (dest, strlen(dest));
   retval->next = next;
+  retval->searched = 0;
 
   return retval;
 }
@@ -243,6 +244,8 @@ cp_copy_usings (struct using_direct *using,
 				    obstack);
       retval->next = cp_copy_usings (using->next, obstack);
 
+      retval->searched = using->searched;
+
       xfree (using->import_src);
       xfree (using->import_dest);
       xfree (using);
@@ -272,7 +275,8 @@ cp_lookup_symbol_nonlocal (const char *name,
   if (sym != NULL)
     return sym;
 
-  return cp_lookup_symbol_namespace (scope, name, linkage_name, block, domain);
+  return cp_lookup_symbol_namespace (scope, name, linkage_name, block, domain,
+                                     1);
 }
 
 /* Look up NAME in the C++ namespace NAMESPACE. Other arguments are as in
@@ -302,19 +306,46 @@ cp_lookup_symbol_in_namespace (const char *namespace,
     }
 }
 
-/* Search for NAME by applying all import statements belonging
-   to BLOCK which are applicable in SCOPE.  */
+/* Used for cleanups to reset the "searched" flag incase
+   of an error.  */
+
+static void
+reset_directive_searched (void *data)
+{
+  struct using_direct *direct = data;
+  direct->searched = 0;
+}
 
+/* Search for NAME by applying all import statements belonging
+   to BLOCK which are applicable in SCOPE.
+   If SEARCH_PARENTS the search will include imports which are applicable in
+   parents of SCOPE.
+   Example:
+
+     namespace A{
+       using namespace X;
+       namespace B{
+         using namespace Y;
+       }
+     }
+
+   If SCOPE is "A::B" and SEARCH_PARENTS is true the imports of namespaces X
+   and Y will be considered. If SEARCH_PARENTS is false only the import of Y
+   is considered.  */
+
 static struct symbol *
 cp_lookup_symbol_imports (const char *scope,
                           const char *name,
                           const char *linkage_name,
                           const struct block *block,
-                          const domain_enum domain)
+                          const domain_enum domain,
+                          const int search_parents)
 {
-  const struct using_direct *current;
+  struct using_direct *current;
   struct symbol *sym;
   int len;
+  int directive_match;
+  struct cleanup *searched_cleanup;
 
   /* First, try to find the symbol in the given namespace.  */
   sym = cp_lookup_symbol_in_namespace (scope, name, linkage_name, block,
@@ -330,24 +361,41 @@ cp_lookup_symbol_imports (const char *scope,
        current != NULL;
        current = current->next)
     {
+      len = strlen (current->import_dest);
+      directive_match = (search_parents
+                         ? (strncmp (scope, current->import_dest,
+                                     strlen (current->import_dest)) == 0
+                            && (len == 0
+                        	 || scope[len] == ':' || scope[len] == '\0'))
+                         : strcmp (scope, current->import_dest) == 0);
 
       /* If the import destination is the current scope or one of its ancestors then
          it is applicable.  */
-      len = strlen (current->import_dest);
-      if (strncmp (scope, current->import_dest, len) == 0
-	  && (len == 0 || scope[len] == ':' || scope[len] == '\0'))
+      if (directive_match && !current->searched)
 	{
-	  sym = cp_lookup_symbol_in_namespace (current->import_src, name,
-					       linkage_name, block, domain);
-	  if (sym != NULL)
-	    return sym;
+	/* Mark this import as searched so that the recursive call does not
+          search it again.  */
+	current->searched = 1;
+	searched_cleanup = make_cleanup (reset_directive_searched, current);
+
+	sym = cp_lookup_symbol_namespace (current->import_src,
+	                                  name,
+	                                  linkage_name,
+	                                  block,
+	                                  domain,
+	                                  0);
+
+	current->searched = 0;
+	discard_cleanups (searched_cleanup);
+
+	if (sym != NULL)
+	  return sym;
 	}
     }
 
   return NULL;
 }
 
-
  /* Searches for NAME in the current namespace, and by applying relevant import
     statements belonging to BLOCK and its parents. SCOPE is the namespace scope
     of the context in which the search is being evaluated.  */
@@ -357,14 +405,16 @@ cp_lookup_symbol_namespace (const char *scope,
                             const char *name,
                             const char *linkage_name,
                             const struct block *block,
-                            const domain_enum domain)
+                            const domain_enum domain,
+                            const int search_parents)
 {
   struct symbol *sym;
 
   /* Search for name in namespaces imported to this and parent blocks.  */
   while (block != NULL)
     {
-      sym = cp_lookup_symbol_imports (scope,name, linkage_name, block, domain);
+      sym = cp_lookup_symbol_imports (scope, name, linkage_name, block, domain,
+                                      search_parents);
 
       if (sym)
 	return sym;
diff --git a/gdb/cp-support.h b/gdb/cp-support.h
index 7ecd201..9400469 100644
--- a/gdb/cp-support.h
+++ b/gdb/cp-support.h
@@ -47,6 +47,9 @@ struct using_direct
   char *import_src;
   char *import_dest;
   struct using_direct *next;
+
+  /* Used during import search to temporarily mark this node as searched.  */
+  int searched;
 };
 
 
@@ -107,7 +110,8 @@ extern struct symbol *cp_lookup_symbol_namespace (const char *namespace,
 						  const char *name,
 						  const char *linkage_name,
 						  const struct block *block,
-						  const domain_enum domain);
+						  const domain_enum domain,
+						  const int search_parents);
 
 extern struct type *cp_lookup_nested_type (struct type *parent_type,
 					   const char *nested_name,
diff --git a/gdb/valops.c b/gdb/valops.c
index 012ea6a..6fdea95 100644
--- a/gdb/valops.c
+++ b/gdb/valops.c
@@ -2765,7 +2765,7 @@ value_maybe_namespace_elt (const struct type *curtype,
 
   sym = cp_lookup_symbol_namespace (namespace_name, name, NULL,
 				    get_selected_block (0),
-				    VAR_DOMAIN);
+				    VAR_DOMAIN, 1);
 
   if (sym == NULL)
     return NULL;

Attachment: sami2-recursive-search.patch
Description: Text document