[patch] Add namespace aliasing support.

[patch] Add namespace aliasing support.

[Sami Wagiaalla]

[-- Attachment #1: Type: text/plain, Size: 8731 bytes --]

gdb/7935

This patch adds support for namespace aliasing.
Eg.

namespace A{
   int x;
}

void foo(){
   namespace B=A
}

...

(gdb) p B::x

PR gdb/7935:
2010-01-29  Sami Wagiaalla  <swagiaal@redhat.com>

    * cp-support.h: Added char* alias element to using_direct data
    struct.
    (cp_add_using): Added char* alias argument.
    (cp_add_using_directive): Ditto.
    * cp-namespace.c: Updated with the above changes.
    (cp_lookup_symbol_imports): Check for aliases.
    * dwarf2read.c (read_import_statement): Figure out local alias
    for the import and pass it on to cp_add_using.
    (read_namespace): Pass alias argument to cp_add_using.
        
2010-01-29  Sami Wagiaalla  <swagiaal@redhat.com>

    * gdb.cp/namespace-using.exp: Removed kfail; bug has been fixed.


diff --git a/gdb/cp-namespace.c b/gdb/cp-namespace.c
index 8ca9c20..a6ecb26 100644
--- a/gdb/cp-namespace.c
+++ b/gdb/cp-namespace.c
@@ -117,7 +117,7 @@ cp_scan_for_anonymous_namespaces (const struct symbol *symbol)
  		 anonymous namespace.  So add symbols in it to the
  		 namespace given by the previous component if there is
  		 one, or to the global namespace if there isn't.  */
-	      cp_add_using_directive (dest, src);
+	      cp_add_using_directive (dest, src, "");
  	    }
  	  /* The "+ 2" is for the "::".  */
  	  previous_component = next_component + 2;
@@ -132,7 +132,7 @@ cp_scan_for_anonymous_namespaces (const struct symbol *symbol)
     has already been added, don't add it twice.  */
  
  void
-cp_add_using_directive (const char *dest, const char *src)
+cp_add_using_directive (const char *dest, const char *src, const char* alias)
  {
    struct using_direct *current;
    struct using_direct *new;
@@ -146,7 +146,7 @@ cp_add_using_directive (const char *dest, const char *src)
  	return;
      }
  
-  using_directives = cp_add_using (dest, src, using_directives);
+  using_directives = cp_add_using (dest, src, alias, using_directives);
  
  }
  
@@ -198,8 +198,10 @@ cp_is_anonymous (const char *namespace)
  	  != NULL);
  }
  
-/* Create a new struct using direct which imports the namespace SRC
-   into the scope DEST.
+/* Create a new struct using direct which imports the namespace SRC into the
+   scope DEST. ALIAS is the name of the imported namespace in the current
+   scope. If ALIAS is an empty string  then the namespace is known by its
+   original name.
     Set its next member in the linked list to NEXT; allocate all memory
     using xmalloc.  It copies the strings, so NAME can be a temporary
     string.  */
@@ -207,6 +209,7 @@ cp_is_anonymous (const char *namespace)
  struct using_direct *
  cp_add_using (const char *dest,
                const char *src,
+              const char *alias,
  	      struct using_direct *next)
  {
    struct using_direct *retval;
@@ -214,6 +217,8 @@ cp_add_using (const char *dest,
    retval = xmalloc (sizeof (struct using_direct));
    retval->import_src = savestring (src, strlen(src));
    retval->import_dest = savestring (dest, strlen(dest));
+  retval->alias = savestring (alias, strlen(alias));
+
    retval->next = next;
    retval->searched = 0;
  
@@ -344,13 +349,28 @@ cp_lookup_symbol_imports (const char *scope,
  	current->searched = 1;
  	searched_cleanup = make_cleanup (reset_directive_searched, current);
  
-	sym = cp_lookup_symbol_namespace (current->import_src,
+	if (strcmp (name, current->alias) == 0)
+	  /* If the import is creating an alias and the alias matches the
+	     sought name. Pass current->import_src as the NAME to direct the
+	     search towards the aliased namespace.   */
+	  {
+	    sym = cp_lookup_symbol_in_namespace (scope,
+	                                         current->import_src,
+	                                         linkage_name,
+	                                         block,
+	                                         domain);
+	  }
+	else if (strcmp ("", current->alias) == 0)
+	  {
+	  /* If this import statement creates no alias, pass current->inner as
+	     NAMESPACE to direct the search towards the imported namespace.  */
+	  sym = cp_lookup_symbol_imports (current->import_src,
  	                                  name,
  	                                  linkage_name,
  	                                  block,
  	                                  domain,
  	                                  0);
-
+	  }
  	current->searched = 0;
  	discard_cleanups (searched_cleanup);
  
diff --git a/gdb/cp-support.h b/gdb/cp-support.h
index 33b1b44..5d28bf9 100644
--- a/gdb/cp-support.h
+++ b/gdb/cp-support.h
@@ -38,14 +38,20 @@ struct demangle_component;
  
  /* This struct is designed to store data from using directives.  It
     says that names from namespace IMPORT_SRC should be visible within
-   namespace IMPORT_DEST. IMPORT_DEST should always be a strict initial
-   substring of IMPORT_SRC. These form a linked list; NEXT is the next element
-   of the list.  */
+   namespace IMPORT_DEST. These form a linked list; NEXT is the next element
+   of the list. ALIAS is set to a non empty string if the imported namespace
+   has been aliased.
+   Eg:
+       namespace C=A::B;
+*/
  
  struct using_direct
  {
    char *import_src;
    char *import_dest;
+
+  char *alias;
+
    struct using_direct *next;
  
    /* Used during import search to temporarily mark this node as searched.  */
@@ -82,10 +88,12 @@ extern int cp_validate_operator (const char *input);
  extern int cp_is_anonymous (const char *namespace);
  
  extern void cp_add_using_directive (const char *dest,
-                                    const char *src);
+                                    const char *src,
+                                    const char *alias);
  
  extern struct using_direct *cp_add_using (const char *dest,
                                            const char *src,
+                                          const char *alias,
  					  struct using_direct *next);
  
  extern void cp_initialize_namespace (void);
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 2f671ca..ae089eb 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -3385,6 +3385,8 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
    struct dwarf2_cu *imported_cu;
    const char *imported_name;
    const char *imported_name_prefix;
+  char *import_alias;
+
    const char *import_prefix;
    char *canonical_name;
  
@@ -3436,7 +3438,12 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
        return;
      }
  
-  /* FIXME: dwarf2_name (die); for the local name after import.  */
+  /* Figure out the local name after import.  */
+  import_alias = dwarf2_name (die, cu);
+  if (import_alias == NULL)
+    {
+    import_alias = "";
+    }
  
    /* Figure out where the statement is being imported to.  */
    import_prefix = determine_prefix (die, cu);
@@ -3447,7 +3454,8 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
  
    if (strlen (imported_name_prefix) > 0)
      {
-      canonical_name = alloca (strlen (imported_name_prefix) + 2 + strlen (imported_name) + 1);
+      canonical_name = alloca (strlen (imported_name_prefix)
+                               + 2 + strlen (imported_name) + 1);
        strcpy (canonical_name, imported_name_prefix);
        strcat (canonical_name, "::");
        strcat (canonical_name, imported_name);
@@ -3458,7 +3466,10 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
        strcpy (canonical_name, imported_name);
      }
  
-  using_directives = cp_add_using (import_prefix,canonical_name, using_directives);
+  using_directives = cp_add_using (import_prefix,
+                                   canonical_name,
+                                   import_alias,
+                                   using_directives);
  }
  
  static void
@@ -5616,7 +5627,7 @@ read_namespace (struct die_info *die, struct dwarf2_cu *cu)
        if (is_anonymous)
  	{
  	  const char *previous_prefix = determine_prefix (die, cu);
-	  cp_add_using_directive (previous_prefix, TYPE_NAME (type));
+	  cp_add_using_directive (previous_prefix, TYPE_NAME (type), "");
  	}
      }
  
diff --git a/gdb/testsuite/gdb.cp/nsusing.exp b/gdb/testsuite/gdb.cp/nsusing.exp
index bd115c4..72a616e 100644
--- a/gdb/testsuite/gdb.cp/nsusing.exp
+++ b/gdb/testsuite/gdb.cp/nsusing.exp
@@ -116,14 +116,11 @@ if ![runto marker2] then {
      continue
  }
  
-setup_kfail "gdb/7935" "*-*-*"
  gdb_test "print B::_a" "= 1"
  
-setup_kfail "gdb/7935" "*-*-*"
  gdb_test "print _a" "No symbol \"_a\" in current context." \
      "print _a in namespace alias scope"
  
-setup_kfail "gdb/7935" "*-*-*"
  gdb_test "print x" "No symbol \"x\" in current context." \
      "print x in namespace alias scope"
  

[-- Attachment #2: namespace-alias.patch --]
[-- Type: text/plain, Size: 7842 bytes --]

diff --git a/gdb/cp-namespace.c b/gdb/cp-namespace.c
index 8ca9c20..a6ecb26 100644
--- a/gdb/cp-namespace.c
+++ b/gdb/cp-namespace.c
@@ -117,7 +117,7 @@ cp_scan_for_anonymous_namespaces (const struct symbol *symbol)
 		 anonymous namespace.  So add symbols in it to the
 		 namespace given by the previous component if there is
 		 one, or to the global namespace if there isn't.  */
-	      cp_add_using_directive (dest, src);
+	      cp_add_using_directive (dest, src, "");
 	    }
 	  /* The "+ 2" is for the "::".  */
 	  previous_component = next_component + 2;
@@ -132,7 +132,7 @@ cp_scan_for_anonymous_namespaces (const struct symbol *symbol)
    has already been added, don't add it twice.  */
 
 void
-cp_add_using_directive (const char *dest, const char *src)
+cp_add_using_directive (const char *dest, const char *src, const char* alias)
 {
   struct using_direct *current;
   struct using_direct *new;
@@ -146,7 +146,7 @@ cp_add_using_directive (const char *dest, const char *src)
 	return;
     }
 
-  using_directives = cp_add_using (dest, src, using_directives);
+  using_directives = cp_add_using (dest, src, alias, using_directives);
 
 }
 
@@ -198,8 +198,10 @@ cp_is_anonymous (const char *namespace)
 	  != NULL);
 }
 
-/* Create a new struct using direct which imports the namespace SRC
-   into the scope DEST.
+/* Create a new struct using direct which imports the namespace SRC into the
+   scope DEST. ALIAS is the name of the imported namespace in the current
+   scope. If ALIAS is an empty string  then the namespace is known by its
+   original name.
    Set its next member in the linked list to NEXT; allocate all memory
    using xmalloc.  It copies the strings, so NAME can be a temporary
    string.  */
@@ -207,6 +209,7 @@ cp_is_anonymous (const char *namespace)
 struct using_direct *
 cp_add_using (const char *dest,
               const char *src,
+              const char *alias,
 	      struct using_direct *next)
 {
   struct using_direct *retval;
@@ -214,6 +217,8 @@ cp_add_using (const char *dest,
   retval = xmalloc (sizeof (struct using_direct));
   retval->import_src = savestring (src, strlen(src));
   retval->import_dest = savestring (dest, strlen(dest));
+  retval->alias = savestring (alias, strlen(alias));
+
   retval->next = next;
   retval->searched = 0;
 
@@ -344,13 +349,28 @@ cp_lookup_symbol_imports (const char *scope,
 	current->searched = 1;
 	searched_cleanup = make_cleanup (reset_directive_searched, current);
 
-	sym = cp_lookup_symbol_namespace (current->import_src,
+	if (strcmp (name, current->alias) == 0)
+	  /* If the import is creating an alias and the alias matches the
+	     sought name. Pass current->import_src as the NAME to direct the
+	     search towards the aliased namespace.   */
+	  {
+	    sym = cp_lookup_symbol_in_namespace (scope,
+	                                         current->import_src,
+	                                         linkage_name,
+	                                         block,
+	                                         domain);
+	  }
+	else if (strcmp ("", current->alias) == 0)
+	  {
+	  /* If this import statement creates no alias, pass current->inner as
+	     NAMESPACE to direct the search towards the imported namespace.  */
+	  sym = cp_lookup_symbol_imports (current->import_src,
 	                                  name,
 	                                  linkage_name,
 	                                  block,
 	                                  domain,
 	                                  0);
-
+	  }
 	current->searched = 0;
 	discard_cleanups (searched_cleanup);
 
diff --git a/gdb/cp-support.h b/gdb/cp-support.h
index 33b1b44..5d28bf9 100644
--- a/gdb/cp-support.h
+++ b/gdb/cp-support.h
@@ -38,14 +38,20 @@ struct demangle_component;
 
 /* This struct is designed to store data from using directives.  It
    says that names from namespace IMPORT_SRC should be visible within
-   namespace IMPORT_DEST. IMPORT_DEST should always be a strict initial
-   substring of IMPORT_SRC. These form a linked list; NEXT is the next element
-   of the list.  */
+   namespace IMPORT_DEST. These form a linked list; NEXT is the next element
+   of the list. ALIAS is set to a non empty string if the imported namespace
+   has been aliased.
+   Eg:
+       namespace C=A::B;
+*/
 
 struct using_direct
 {
   char *import_src;
   char *import_dest;
+
+  char *alias;
+
   struct using_direct *next;
 
   /* Used during import search to temporarily mark this node as searched.  */
@@ -82,10 +88,12 @@ extern int cp_validate_operator (const char *input);
 extern int cp_is_anonymous (const char *namespace);
 
 extern void cp_add_using_directive (const char *dest,
-                                    const char *src);
+                                    const char *src,
+                                    const char *alias);
 
 extern struct using_direct *cp_add_using (const char *dest,
                                           const char *src,
+                                          const char *alias,
 					  struct using_direct *next);
 
 extern void cp_initialize_namespace (void);
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 2f671ca..ae089eb 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -3385,6 +3385,8 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
   struct dwarf2_cu *imported_cu;
   const char *imported_name;
   const char *imported_name_prefix;
+  char *import_alias;
+
   const char *import_prefix;
   char *canonical_name;
 
@@ -3436,7 +3438,12 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
       return;
     }
 
-  /* FIXME: dwarf2_name (die); for the local name after import.  */
+  /* Figure out the local name after import.  */
+  import_alias = dwarf2_name (die, cu);
+  if (import_alias == NULL)
+    {
+    import_alias = "";
+    }
 
   /* Figure out where the statement is being imported to.  */
   import_prefix = determine_prefix (die, cu);
@@ -3447,7 +3454,8 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
 
   if (strlen (imported_name_prefix) > 0)
     {
-      canonical_name = alloca (strlen (imported_name_prefix) + 2 + strlen (imported_name) + 1);
+      canonical_name = alloca (strlen (imported_name_prefix)
+                               + 2 + strlen (imported_name) + 1);
       strcpy (canonical_name, imported_name_prefix);
       strcat (canonical_name, "::");
       strcat (canonical_name, imported_name);
@@ -3458,7 +3466,10 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
       strcpy (canonical_name, imported_name);
     }
 
-  using_directives = cp_add_using (import_prefix,canonical_name, using_directives);
+  using_directives = cp_add_using (import_prefix,
+                                   canonical_name,
+                                   import_alias,
+                                   using_directives);
 }
 
 static void
@@ -5616,7 +5627,7 @@ read_namespace (struct die_info *die, struct dwarf2_cu *cu)
       if (is_anonymous)
 	{
 	  const char *previous_prefix = determine_prefix (die, cu);
-	  cp_add_using_directive (previous_prefix, TYPE_NAME (type));
+	  cp_add_using_directive (previous_prefix, TYPE_NAME (type), "");
 	}
     }
 
diff --git a/gdb/testsuite/gdb.cp/nsusing.exp b/gdb/testsuite/gdb.cp/nsusing.exp
index bd115c4..72a616e 100644
--- a/gdb/testsuite/gdb.cp/nsusing.exp
+++ b/gdb/testsuite/gdb.cp/nsusing.exp
@@ -116,14 +116,11 @@ if ![runto marker2] then {
     continue
 }
 
-setup_kfail "gdb/7935" "*-*-*"
 gdb_test "print B::_a" "= 1"
 
-setup_kfail "gdb/7935" "*-*-*"
 gdb_test "print _a" "No symbol \"_a\" in current context." \
     "print _a in namespace alias scope"
 
-setup_kfail "gdb/7935" "*-*-*"
 gdb_test "print x" "No symbol \"x\" in current context." \
     "print x in namespace alias scope"
 

Re: [patch] Add namespace aliasing support.

[Tom Tromey]

>>>>> "Sami" == Sami Wagiaalla <swagiaal@redhat.com> writes:

Sami> 2010-01-29  Sami Wagiaalla  <swagiaal@redhat.com>
Sami>    * cp-support.h: Added char* alias element to using_direct data
Sami>    struct.
Sami>    (cp_add_using): Added char* alias argument.
Sami>    (cp_add_using_directive): Ditto.
Sami>    * cp-namespace.c: Updated with the above changes.
Sami>    (cp_lookup_symbol_imports): Check for aliases.
Sami>    * dwarf2read.c (read_import_statement): Figure out local alias
Sami>    for the import and pass it on to cp_add_using.
Sami>    (read_namespace): Pass alias argument to cp_add_using.
Sami>        2010-01-29  Sami Wagiaalla  <swagiaal@redhat.com>

Lots of formatting nits, plus one slightly more substantial comment.

Sami> +cp_add_using_directive (const char *dest, const char *src, const char* alias)

"char *", not "char*".

Sami> +   scope DEST. ALIAS is the name of the imported namespace in the current
Sami> +   scope. If ALIAS is an empty string  then the namespace is known by its
Sami> +   original name.

Two spaces after a period.  Only one space between "string then".

Sami> +  retval->alias = savestring (alias, strlen(alias));

Space before open paren.

Sami> +	else if (strcmp ("", current->alias) == 0)

It is more idiomatic in C to use NULL rather than the empty string as a
special value.  Please make this change.

Sami> +	  {
Sami> +	  /* If this import statement creates no alias, pass current->inner as
Sami> +	     NAMESPACE to direct the search towards the imported namespace.  */
Sami> +	  sym = cp_lookup_symbol_imports (current->import_src,

The code here should be indented 2 spaces beyond the open brace, not
lined up with it.

Sami> +   namespace IMPORT_DEST. These form a linked list; NEXT is the next element
Sami> +   of the list. ALIAS is set to a non empty string if the imported namespace
Sami> +   has been aliased.

The period rule again.

Sami> +  import_alias = dwarf2_name (die, cu);
Sami> +  if (import_alias == NULL)
Sami> +    {
Sami> +    import_alias = "";
Sami> +    }

This code will be going away, but just FYI, don't brace a single
statement.

Tom

Re: [patch] Add namespace aliasing support.

[Sami Wagiaalla]

[-- Attachment #1: Type: text/plain, Size: 8899 bytes --]

Thanks for the prompt review. Here is the corrected patch:

PR gdb/7935:
2010-02-01  Sami Wagiaalla  <swagiaal@redhat.com>

    * cp-support.h: Added char* alias element to using_direct data
    struct.
    (cp_add_using): Added char* alias argument.
    (cp_add_using_directive): Ditto.
    * cp-namespace.c: Updated with the above changes.
    (cp_lookup_symbol_imports): Check for aliases.
    * dwarf2read.c (read_import_statement): Figure out local alias
    for the import and pass it on to cp_add_using.
    (read_namespace): Pass alias argument to cp_add_using.

2010-02-01  Sami Wagiaalla  <swagiaal@redhat.com>

    * gdb.cp/namespace-using.exp: Removed kfail; bug has been fixed.



diff --git a/gdb/cp-namespace.c b/gdb/cp-namespace.c
index 8ca9c20..e0eb151 100644
--- a/gdb/cp-namespace.c
+++ b/gdb/cp-namespace.c
@@ -117,7 +117,7 @@ cp_scan_for_anonymous_namespaces (const struct symbol *symbol)
  		 anonymous namespace.  So add symbols in it to the
  		 namespace given by the previous component if there is
  		 one, or to the global namespace if there isn't.  */
-	      cp_add_using_directive (dest, src);
+	      cp_add_using_directive (dest, src, NULL);
  	    }
  	  /* The "+ 2" is for the "::".  */
  	  previous_component = next_component + 2;
@@ -132,7 +132,7 @@ cp_scan_for_anonymous_namespaces (const struct symbol *symbol)
     has already been added, don't add it twice.  */
  
  void
-cp_add_using_directive (const char *dest, const char *src)
+cp_add_using_directive (const char *dest, const char *src, const char *alias)
  {
    struct using_direct *current;
    struct using_direct *new;
@@ -146,7 +146,7 @@ cp_add_using_directive (const char *dest, const char *src)
  	return;
      }
  
-  using_directives = cp_add_using (dest, src, using_directives);
+  using_directives = cp_add_using (dest, src, alias, using_directives);
  
  }
  
@@ -198,8 +198,10 @@ cp_is_anonymous (const char *namespace)
  	  != NULL);
  }
  
-/* Create a new struct using direct which imports the namespace SRC
-   into the scope DEST.
+/* Create a new struct using direct which imports the namespace SRC into the
+   scope DEST.  ALIAS is the name of the imported namespace in the current
+   scope.  If ALIAS is an empty string then the namespace is known by its
+   original name.
     Set its next member in the linked list to NEXT; allocate all memory
     using xmalloc.  It copies the strings, so NAME can be a temporary
     string.  */
@@ -207,6 +209,7 @@ cp_is_anonymous (const char *namespace)
  struct using_direct *
  cp_add_using (const char *dest,
                const char *src,
+              const char *alias,
  	      struct using_direct *next)
  {
    struct using_direct *retval;
@@ -214,6 +217,12 @@ cp_add_using (const char *dest,
    retval = xmalloc (sizeof (struct using_direct));
    retval->import_src = savestring (src, strlen(src));
    retval->import_dest = savestring (dest, strlen(dest));
+
+  if (alias != NULL)
+    retval->alias = savestring (alias, strlen (alias));
+  else
+    retval->alias = NULL;
+
    retval->next = next;
    retval->searched = 0;
  
@@ -344,13 +353,28 @@ cp_lookup_symbol_imports (const char *scope,
  	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);
-
+	if (current->alias != NULL && strcmp (name, current->alias) == 0)
+	  /* If the import is creating an alias and the alias matches the
+	     sought name.  Pass current->import_src as the NAME to direct the
+	     search towards the aliased namespace.  */
+	  {
+	    sym = cp_lookup_symbol_in_namespace (scope,
+	                                         current->import_src,
+	                                         linkage_name,
+	                                         block,
+	                                         domain);
+	  }
+	else if (current->alias == NULL)
+	  {
+	    /* If this import statement creates no alias, pass current->inner as
+               NAMESPACE to direct the search towards the imported namespace.  */
+	    sym = cp_lookup_symbol_imports (current->import_src,
+	                                    name,
+	                                    linkage_name,
+	                                    block,
+	                                    domain,
+	                                    0);
+	  }
  	current->searched = 0;
  	discard_cleanups (searched_cleanup);
  
diff --git a/gdb/cp-support.h b/gdb/cp-support.h
index 33b1b44..44d6ad4 100644
--- a/gdb/cp-support.h
+++ b/gdb/cp-support.h
@@ -38,14 +38,20 @@ struct demangle_component;
  
  /* This struct is designed to store data from using directives.  It
     says that names from namespace IMPORT_SRC should be visible within
-   namespace IMPORT_DEST. IMPORT_DEST should always be a strict initial
-   substring of IMPORT_SRC. These form a linked list; NEXT is the next element
-   of the list.  */
+   namespace IMPORT_DEST.  These form a linked list; NEXT is the next element
+   of the list.  ALIAS is set to a non empty string if the imported namespace
+   has been aliased.
+   Eg:
+       namespace C=A::B;
+*/
  
  struct using_direct
  {
    char *import_src;
    char *import_dest;
+
+  char *alias;
+
    struct using_direct *next;
  
    /* Used during import search to temporarily mark this node as searched.  */
@@ -82,10 +88,12 @@ extern int cp_validate_operator (const char *input);
  extern int cp_is_anonymous (const char *namespace);
  
  extern void cp_add_using_directive (const char *dest,
-                                    const char *src);
+                                    const char *src,
+                                    const char *alias);
  
  extern struct using_direct *cp_add_using (const char *dest,
                                            const char *src,
+                                          const char *alias,
  					  struct using_direct *next);
  
  extern void cp_initialize_namespace (void);
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 2f671ca..46b9efc 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -3385,6 +3385,8 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
    struct dwarf2_cu *imported_cu;
    const char *imported_name;
    const char *imported_name_prefix;
+  char *import_alias;
+
    const char *import_prefix;
    char *canonical_name;
  
@@ -3436,7 +3438,8 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
        return;
      }
  
-  /* FIXME: dwarf2_name (die); for the local name after import.  */
+  /* Figure out the local name after import.  */
+  import_alias = dwarf2_name (die, cu);
  
    /* Figure out where the statement is being imported to.  */
    import_prefix = determine_prefix (die, cu);
@@ -3447,7 +3450,8 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
  
    if (strlen (imported_name_prefix) > 0)
      {
-      canonical_name = alloca (strlen (imported_name_prefix) + 2 + strlen (imported_name) + 1);
+      canonical_name = alloca (strlen (imported_name_prefix)
+                               + 2 + strlen (imported_name) + 1);
        strcpy (canonical_name, imported_name_prefix);
        strcat (canonical_name, "::");
        strcat (canonical_name, imported_name);
@@ -3458,7 +3462,10 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
        strcpy (canonical_name, imported_name);
      }
  
-  using_directives = cp_add_using (import_prefix,canonical_name, using_directives);
+  using_directives = cp_add_using (import_prefix,
+                                   canonical_name,
+                                   import_alias,
+                                   using_directives);
  }
  
  static void
@@ -5616,7 +5623,7 @@ read_namespace (struct die_info *die, struct dwarf2_cu *cu)
        if (is_anonymous)
  	{
  	  const char *previous_prefix = determine_prefix (die, cu);
-	  cp_add_using_directive (previous_prefix, TYPE_NAME (type));
+	  cp_add_using_directive (previous_prefix, TYPE_NAME (type), NULL);
  	}
      }
  
diff --git a/gdb/testsuite/gdb.cp/nsusing.exp b/gdb/testsuite/gdb.cp/nsusing.exp
index bd115c4..72a616e 100644
--- a/gdb/testsuite/gdb.cp/nsusing.exp
+++ b/gdb/testsuite/gdb.cp/nsusing.exp
@@ -116,14 +116,11 @@ if ![runto marker2] then {
      continue
  }
  
-setup_kfail "gdb/7935" "*-*-*"
  gdb_test "print B::_a" "= 1"
  
-setup_kfail "gdb/7935" "*-*-*"
  gdb_test "print _a" "No symbol \"_a\" in current context." \
      "print _a in namespace alias scope"
  
-setup_kfail "gdb/7935" "*-*-*"
  gdb_test "print x" "No symbol \"x\" in current context." \
      "print x in namespace alias scope"
  

[-- Attachment #2: namespace-alias.patch --]
[-- Type: text/plain, Size: 8102 bytes --]

diff --git a/gdb/cp-namespace.c b/gdb/cp-namespace.c
index 8ca9c20..e0eb151 100644
--- a/gdb/cp-namespace.c
+++ b/gdb/cp-namespace.c
@@ -117,7 +117,7 @@ cp_scan_for_anonymous_namespaces (const struct symbol *symbol)
 		 anonymous namespace.  So add symbols in it to the
 		 namespace given by the previous component if there is
 		 one, or to the global namespace if there isn't.  */
-	      cp_add_using_directive (dest, src);
+	      cp_add_using_directive (dest, src, NULL);
 	    }
 	  /* The "+ 2" is for the "::".  */
 	  previous_component = next_component + 2;
@@ -132,7 +132,7 @@ cp_scan_for_anonymous_namespaces (const struct symbol *symbol)
    has already been added, don't add it twice.  */
 
 void
-cp_add_using_directive (const char *dest, const char *src)
+cp_add_using_directive (const char *dest, const char *src, const char *alias)
 {
   struct using_direct *current;
   struct using_direct *new;
@@ -146,7 +146,7 @@ cp_add_using_directive (const char *dest, const char *src)
 	return;
     }
 
-  using_directives = cp_add_using (dest, src, using_directives);
+  using_directives = cp_add_using (dest, src, alias, using_directives);
 
 }
 
@@ -198,8 +198,10 @@ cp_is_anonymous (const char *namespace)
 	  != NULL);
 }
 
-/* Create a new struct using direct which imports the namespace SRC
-   into the scope DEST.
+/* Create a new struct using direct which imports the namespace SRC into the
+   scope DEST.  ALIAS is the name of the imported namespace in the current
+   scope.  If ALIAS is an empty string then the namespace is known by its
+   original name.
    Set its next member in the linked list to NEXT; allocate all memory
    using xmalloc.  It copies the strings, so NAME can be a temporary
    string.  */
@@ -207,6 +209,7 @@ cp_is_anonymous (const char *namespace)
 struct using_direct *
 cp_add_using (const char *dest,
               const char *src,
+              const char *alias,
 	      struct using_direct *next)
 {
   struct using_direct *retval;
@@ -214,6 +217,12 @@ cp_add_using (const char *dest,
   retval = xmalloc (sizeof (struct using_direct));
   retval->import_src = savestring (src, strlen(src));
   retval->import_dest = savestring (dest, strlen(dest));
+
+  if (alias != NULL)
+    retval->alias = savestring (alias, strlen (alias));
+  else
+    retval->alias = NULL;
+
   retval->next = next;
   retval->searched = 0;
 
@@ -344,13 +353,28 @@ cp_lookup_symbol_imports (const char *scope,
 	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);
-
+	if (current->alias != NULL && strcmp (name, current->alias) == 0)
+	  /* If the import is creating an alias and the alias matches the
+	     sought name.  Pass current->import_src as the NAME to direct the
+	     search towards the aliased namespace.  */
+	  {
+	    sym = cp_lookup_symbol_in_namespace (scope,
+	                                         current->import_src,
+	                                         linkage_name,
+	                                         block,
+	                                         domain);
+	  }
+	else if (current->alias == NULL)
+	  {
+	    /* If this import statement creates no alias, pass current->inner as
+               NAMESPACE to direct the search towards the imported namespace.  */
+	    sym = cp_lookup_symbol_imports (current->import_src,
+	                                    name,
+	                                    linkage_name,
+	                                    block,
+	                                    domain,
+	                                    0);
+	  }
 	current->searched = 0;
 	discard_cleanups (searched_cleanup);
 
diff --git a/gdb/cp-support.h b/gdb/cp-support.h
index 33b1b44..44d6ad4 100644
--- a/gdb/cp-support.h
+++ b/gdb/cp-support.h
@@ -38,14 +38,20 @@ struct demangle_component;
 
 /* This struct is designed to store data from using directives.  It
    says that names from namespace IMPORT_SRC should be visible within
-   namespace IMPORT_DEST. IMPORT_DEST should always be a strict initial
-   substring of IMPORT_SRC. These form a linked list; NEXT is the next element
-   of the list.  */
+   namespace IMPORT_DEST.  These form a linked list; NEXT is the next element
+   of the list.  ALIAS is set to a non empty string if the imported namespace
+   has been aliased.
+   Eg:
+       namespace C=A::B;
+*/
 
 struct using_direct
 {
   char *import_src;
   char *import_dest;
+
+  char *alias;
+
   struct using_direct *next;
 
   /* Used during import search to temporarily mark this node as searched.  */
@@ -82,10 +88,12 @@ extern int cp_validate_operator (const char *input);
 extern int cp_is_anonymous (const char *namespace);
 
 extern void cp_add_using_directive (const char *dest,
-                                    const char *src);
+                                    const char *src,
+                                    const char *alias);
 
 extern struct using_direct *cp_add_using (const char *dest,
                                           const char *src,
+                                          const char *alias,
 					  struct using_direct *next);
 
 extern void cp_initialize_namespace (void);
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 2f671ca..46b9efc 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -3385,6 +3385,8 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
   struct dwarf2_cu *imported_cu;
   const char *imported_name;
   const char *imported_name_prefix;
+  char *import_alias;
+
   const char *import_prefix;
   char *canonical_name;
 
@@ -3436,7 +3438,8 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
       return;
     }
 
-  /* FIXME: dwarf2_name (die); for the local name after import.  */
+  /* Figure out the local name after import.  */
+  import_alias = dwarf2_name (die, cu);
 
   /* Figure out where the statement is being imported to.  */
   import_prefix = determine_prefix (die, cu);
@@ -3447,7 +3450,8 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
 
   if (strlen (imported_name_prefix) > 0)
     {
-      canonical_name = alloca (strlen (imported_name_prefix) + 2 + strlen (imported_name) + 1);
+      canonical_name = alloca (strlen (imported_name_prefix)
+                               + 2 + strlen (imported_name) + 1);
       strcpy (canonical_name, imported_name_prefix);
       strcat (canonical_name, "::");
       strcat (canonical_name, imported_name);
@@ -3458,7 +3462,10 @@ read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
       strcpy (canonical_name, imported_name);
     }
 
-  using_directives = cp_add_using (import_prefix,canonical_name, using_directives);
+  using_directives = cp_add_using (import_prefix,
+                                   canonical_name,
+                                   import_alias,
+                                   using_directives);
 }
 
 static void
@@ -5616,7 +5623,7 @@ read_namespace (struct die_info *die, struct dwarf2_cu *cu)
       if (is_anonymous)
 	{
 	  const char *previous_prefix = determine_prefix (die, cu);
-	  cp_add_using_directive (previous_prefix, TYPE_NAME (type));
+	  cp_add_using_directive (previous_prefix, TYPE_NAME (type), NULL);
 	}
     }
 
diff --git a/gdb/testsuite/gdb.cp/nsusing.exp b/gdb/testsuite/gdb.cp/nsusing.exp
index bd115c4..72a616e 100644
--- a/gdb/testsuite/gdb.cp/nsusing.exp
+++ b/gdb/testsuite/gdb.cp/nsusing.exp
@@ -116,14 +116,11 @@ if ![runto marker2] then {
     continue
 }
 
-setup_kfail "gdb/7935" "*-*-*"
 gdb_test "print B::_a" "= 1"
 
-setup_kfail "gdb/7935" "*-*-*"
 gdb_test "print _a" "No symbol \"_a\" in current context." \
     "print _a in namespace alias scope"
 
-setup_kfail "gdb/7935" "*-*-*"
 gdb_test "print x" "No symbol \"x\" in current context." \
     "print x in namespace alias scope"
 

Re: [patch] Add namespace aliasing support.

[Tom Tromey]

>>>>> "Sami" == Sami Wagiaalla <swagiaal@redhat.com> writes:

Sami> 2010-02-01  Sami Wagiaalla  <swagiaal@redhat.com>
Sami>    * cp-support.h: Added char* alias element to using_direct data
Sami>    struct.

I noticed that an earlier ChangeLog entry of yours (in testsuite) had 4
leading spaces rather than a tab.  This one seems to have the same
problem, at least if you cut-and-pasted it; please fix before
committing.

Also, put the PR number into the ChangeLog entry and the commit.  You
can see the existing ChangeLog for some examples of the formatting.
Putting it in the ChangeLog just makes the entry a little more useful;
putting it into the commit message will make some info about the commit
be automatically appended to the PR.

Sami> +   scope.  If ALIAS is an empty string then the namespace is known by its
Sami> +   original name.

This should say something like:  If ALIAS is not null, then ...

Sami> +   of the list.  ALIAS is set to a non empty string if the imported namespace
Sami> +   has been aliased.

Likewise.

This patch is ok with those things fixed.  Thanks.

Tom

Re: [patch] Add namespace aliasing support.

[Doug Evans]

On Tue, Feb 2, 2010 at 11:23 AM, Tom Tromey <tromey@redhat.com> wrote:
>>>>>> "Sami" == Sami Wagiaalla <swagiaal@redhat.com> writes:
>
> Sami> 2010-02-01  Sami Wagiaalla  <swagiaal@redhat.com>
> Sami>    * cp-support.h: Added char* alias element to using_direct data
> Sami>    struct.
>
> I noticed that an earlier ChangeLog entry of yours (in testsuite) had 4
> leading spaces rather than a tab.  This one seems to have the same
> problem, at least if you cut-and-pasted it; please fix before
> committing.
>
> Also, put the PR number into the ChangeLog entry and the commit.  You
> can see the existing ChangeLog for some examples of the formatting.
> Putting it in the ChangeLog just makes the entry a little more useful;
> putting it into the commit message will make some info about the commit
> be automatically appended to the PR.
>
> Sami> +   scope.  If ALIAS is an empty string then the namespace is known by its
> Sami> +   original name.
>
> This should say something like:  If ALIAS is not null, then ...
>
> Sami> +   of the list.  ALIAS is set to a non empty string if the imported namespace
> Sami> +   has been aliased.
>
> Likewise.
>
> This patch is ok with those things fixed.  Thanks.
>
> Tom
>

Sorry for coming into this late.  NEWS entry?
[I mention it because I find the NEWS file really useful.]

Re: [patch] Add namespace aliasing support.

[Tom Tromey]

>>>>> "Doug" == Doug Evans <dje@google.com> writes:

Doug> Sorry for coming into this late.  NEWS entry?
Doug> [I mention it because I find the NEWS file really useful.]

Good idea.  And you had asked me for a NEWS entry for the C++ cast
operator patch ... maybe we should add a section for C++ improvements.

Tom

Re: [patch] Add namespace aliasing support.

[Sami Wagiaalla]

On 02/08/2010 08:38 PM, Tom Tromey wrote:
>>>>>> "Doug" == Doug Evans<dje@google.com>  writes:
>
> Doug>  Sorry for coming into this late.  NEWS entry?
> Doug>  [I mention it because I find the NEWS file really useful.]
>
> Good idea.  And you had asked me for a NEWS entry for the C++ cast
> operator patch ... maybe we should add a section for C++ improvements.
>

Sure, I could add a NEWS entry.

Re: [patch] Add namespace aliasing support.

[Sami Wagiaalla]

> Sorry for coming into this late.  NEWS entry?
> [I mention it because I find the NEWS file really useful.]

How is this ?

Index: gdb/NEWS
===================================================================
RCS file: /cvs/src/src/gdb/NEWS,v
retrieving revision 1.352
diff -u -r1.352 NEWS
--- gdb/NEWS	19 Jan 2010 10:40:06 -0000	1.352
+++ gdb/NEWS	9 Feb 2010 19:34:46 -0000
@@ -3,6 +3,14 @@
 
 *** Changes since GDB 7.0
 
+* Namespace Support
+
+  GDB now supports importing of namespaces in c++. This enables the 
+  user to inspect variables from imported namespaces. Support for
+  namepace aliasing has also been added. So, if a namespace is 
+  aliased in the current scope (e.g. namepace C=A; ) the user can 
+  print variables using the alias (e.g. (gdb) print C::x).
+
 * New targets
 
 Xilinx MicroBlaze		microblaze-*-*

Re: [patch] Add namespace aliasing support.

[Eli Zaretskii]

> Date: Tue, 09 Feb 2010 14:37:32 -0500
> From: Sami Wagiaalla <swagiaal@redhat.com>
> CC: tromey@redhat.com, gdb-patches <gdb-patches@sourceware.org>
> 
> 
> > Sorry for coming into this late.  NEWS entry?
> > [I mention it because I find the NEWS file really useful.]
> 
> How is this ?

Thanks.

> +  GDB now supports importing of namespaces in c++. This enables the 

"C++"

> +  user to inspect variables from imported namespaces. Support for

Two spaces between sentences, please (here and elsewhere).

Okay with these changes.