Re: [PATCH 1/2] namespace support

[Sami Wagiaalla <swagiaal@redhat.com>]

Ping

Sami Wagiaalla wrote:
> 
> Currently imports statements are stored in the nearest static
> block. Also, these import statements only correspond to the
> implicit importing of annonymous namespaces.
> 
> This patch enables each block to own its own 'using
> directives', and creates using directives for non anonymous
> imports.
> 
> 
> 
> diff --git a/gdb/ChangeLog b/gdb/ChangeLog
> index cf44f2a..4614659 100644
> --- a/gdb/ChangeLog
> +++ b/gdb/ChangeLog
> @@ -1,3 +1,26 @@
> +2009-05-21  Sami Wagiaalla  <swagiaal@redhat.com>
> +
> +    * dwarf2read.c (process_die): Handle import statements
> +    (DW_TAG_imported_declaration, case DW_TAG_imported_module)
> +    (read_import_statement): New.
> +    (read_func_scope): Update using_directives to point to current context
> +    (read_lexical_block_scope): Ditto.
> +    * cp-support.h: Added prototype for cp_add_using.
> +    * cp-namespace.c: Removed local context_stack.
> +    (cp_initialize_namespace): Deleted.
> +    (cp_finalize_namespace): Deleted.
> +    (cp_add_using_directive): Use using_directives instead of using_list.
> +    (cp_add_using): No longer static.
> +    * buildsym.h: Created global using_direct variable.
> +    Created using_direct variable in context_stack.
> +    * buildsym.c (finish_block): Set using directives for the block    
> under
> +    construction.
> +    (start_symtab): Removed call to cp_initialize_namespace().
> +    (end_symtab): Removed call to cp_finalize_namespace().
> +    (push_context): Save and reset using_directives.
> +    * block.c (block_using): Return using directives for given
> +    block instead of static block.
> +
>  2009-05-19  Jan Kratochvil  <jan.kratochvil@redhat.com>
> 
>      Remove the PROT parameter from openp.
> diff --git a/gdb/block.c b/gdb/block.c
> index 8f0140c..da36f7c 100644
> --- a/gdb/block.c
> +++ b/gdb/block.c
> @@ -206,25 +206,17 @@ block_set_scope (struct block *block, const char 
> *scope,
>    BLOCK_NAMESPACE (block)->scope = scope;
>  }
> 
> -/* This returns the first using directives associated to BLOCK, if
> -   any.  */
> -
> -/* FIXME: carlton/2003-04-23: This uses the fact that we currently
> -   only have using directives in static blocks, because we only
> -   generate using directives from anonymous namespaces.  Eventually,
> -   when we support using directives everywhere, we'll want to replace
> -   this by some iterator functions.  */
> +/* This returns the using directives list associated to BLOCK, if
> +   any.  Each BLOCK_NAMESPACE()->USING already contains all the namespaces
> +   imported at that code point - even those from its parent blocks.  */
> 
>  struct using_direct *
>  block_using (const struct block *block)
>  {
> -  const struct block *static_block = block_static_block (block);
> -
> -  if (static_block == NULL
> -      || BLOCK_NAMESPACE (static_block) == NULL)
> +  if (block == NULL || BLOCK_NAMESPACE (block) == NULL)
>      return NULL;
>    else
> -    return BLOCK_NAMESPACE (static_block)->using;
> +    return BLOCK_NAMESPACE (block)->using;
>  }
> 
>  /* Set BLOCK's using member to USING; if needed, allocate memory via
> diff --git a/gdb/buildsym.c b/gdb/buildsym.c
> index 6de817f..8c4f53b 100644
> --- a/gdb/buildsym.c
> +++ b/gdb/buildsym.c
> @@ -384,6 +384,8 @@ finish_block (struct symbol *symbol, struct pending 
> **listhead,
>        opblock = pblock;
>      }
> 
> +  block_set_using (block, using_directives, &objfile->objfile_obstack);
> +
>    record_pending_block (objfile, block, opblock);
> 
>    return block;
> @@ -815,10 +817,6 @@ start_symtab (char *name, char *dirname, CORE_ADDR 
> start_addr)
>    /* We shouldn't have any address map at this point.  */
>    gdb_assert (! pending_addrmap);
> 
> -  /* Set up support for C++ namespace support, in case we need it.  */
> -
> -  cp_initialize_namespace ();
> -
>    /* Initialize the list of sub source files with one entry for this
>       file (the top-level source file).  */
> 
> @@ -1015,8 +1013,6 @@ end_symtab (CORE_ADDR end_addr, struct objfile 
> *objfile, int section)
>        finish_block (0, &global_symbols, 0, last_source_start_addr, 
> end_addr,
>              objfile);
>        blockvector = make_blockvector (objfile);
> -      cp_finalize_namespace (BLOCKVECTOR_BLOCK (blockvector, 
> STATIC_BLOCK),
> -                 &objfile->objfile_obstack);
>      }
> 
>    /* Read the line table if it has to be read separately.  */
> @@ -1228,10 +1224,12 @@ push_context (int desc, CORE_ADDR valu)
>    new->params = param_symbols;
>    new->old_blocks = pending_blocks;
>    new->start_addr = valu;
> +  new->using_directives = using_directives;
>    new->name = NULL;
> 
>    local_symbols = NULL;
>    param_symbols = NULL;
> +  using_directives = NULL;
> 
>    return new;
>  }
> diff --git a/gdb/buildsym.h b/gdb/buildsym.h
> index bf23ecc..f542aca 100644
> --- a/gdb/buildsym.h
> +++ b/gdb/buildsym.h
> @@ -125,6 +125,10 @@ EXTERN struct pending *local_symbols;
> 
>  EXTERN struct pending *param_symbols;
> 
> +/* using directives local to lexical context */
> +
> +EXTERN struct using_direct *using_directives;
> +
>  /* Stack representing unclosed lexical contexts (that will become
>     blocks, eventually).  */
> 
> @@ -138,6 +142,10 @@ struct context_stack
> 
>      struct pending *params;
> 
> +    /* Pending using directives at the time we entered */
> +
> +    struct using_direct *using_directives;
> +
>      /* Pointer into blocklist as of entry */
> 
>      struct pending_block *old_blocks;
> diff --git a/gdb/cp-namespace.c b/gdb/cp-namespace.c
> index c6c5617..8bb341f 100644
> --- a/gdb/cp-namespace.c
> +++ b/gdb/cp-namespace.c
> @@ -30,15 +30,7 @@
>  #include "dictionary.h"
>  #include "command.h"
>  #include "frame.h"
> -
> -/* List of using directives that are active in the current file.  */
> -
> -static struct using_direct *using_list;
> -
> -static struct using_direct *cp_add_using (const char *name,
> -                      unsigned int inner_len,
> -                      unsigned int outer_len,
> -                      struct using_direct *next);
> +#include "buildsym.h"
> 
>  static struct using_direct *cp_copy_usings (struct using_direct *using,
>                          struct obstack *obstack);
> @@ -78,31 +70,6 @@ static struct symbol 
> *lookup_possible_namespace_symbol (const char *name);
> 
>  static void maintenance_cplus_namespace (char *args, int from_tty);
> 
> -/* Set up support for dealing with C++ namespace info in the current
> -   symtab.  */
> -
> -void cp_initialize_namespace ()
> -{
> -  using_list = NULL;
> -}
> -
> -/* Add all the using directives we've gathered to the current symtab.
> -   STATIC_BLOCK should be the symtab's static block; OBSTACK is used
> -   for allocation.  */
> -
> -void
> -cp_finalize_namespace (struct block *static_block,
> -               struct obstack *obstack)
> -{
> -  if (using_list != NULL)
> -    {
> -      block_set_using (static_block,
> -               cp_copy_usings (using_list, obstack),
> -               obstack);
> -      using_list = NULL;
> -    }
> -}
> -
>  /* Check to see if SYMBOL refers to an object contained within an
>     anonymous namespace; if so, add an appropriate using directive.  */
> 
> @@ -170,7 +137,7 @@ cp_add_using_directive (const char *name, unsigned 
> int outer_length,
> 
>    /* Has it already been added?  */
> 
> -  for (current = using_list; current != NULL; current = current->next)
> +  for (current = using_directives; current != NULL; current = 
> current->next)
>      {
>        if ((strncmp (current->inner, name, inner_length) == 0)
>        && (strlen (current->inner) == inner_length)
> @@ -178,8 +145,8 @@ cp_add_using_directive (const char *name, unsigned 
> int outer_length,
>      return;
>      }
> 
> -  using_list = cp_add_using (name, inner_length, outer_length,
> -                 using_list);
> +  using_directives = cp_add_using (name, inner_length, outer_length,
> +      using_directives);
>  }
> 
>  /* Record the namespace that the function defined by SYMBOL was
> @@ -237,7 +204,7 @@ cp_is_anonymous (const char *namespace)
>     using xmalloc.  It copies the strings, so NAME can be a temporary
>     string.  */
> 
> -static struct using_direct *
> +struct using_direct *
>  cp_add_using (const char *name,
>            unsigned int inner_len,
>            unsigned int outer_len,
> diff --git a/gdb/cp-support.h b/gdb/cp-support.h
> index 837ca6c..e577f7d 100644
> --- a/gdb/cp-support.h
> +++ b/gdb/cp-support.h
> @@ -80,6 +80,11 @@ extern void cp_add_using_directive (const char *name,
>                      unsigned int outer_length,
>                      unsigned int inner_length);
> 
> +extern struct using_direct *cp_add_using (const char *name,
> +                      unsigned int inner_len,
> +                      unsigned int outer_len,
> +                      struct using_direct *next);
> +
>  extern void cp_initialize_namespace (void);
> 
>  extern void cp_finalize_namespace (struct block *static_block,
> diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
> index 6ddaecd..dd7cf67 100644
> --- a/gdb/dwarf2read.c
> +++ b/gdb/dwarf2read.c
> @@ -971,6 +971,8 @@ static void read_namespace (struct die_info *die, 
> struct dwarf2_cu *);
> 
>  static void read_module (struct die_info *die, struct dwarf2_cu *cu);
> 
> +static void read_import_statement (struct die_info *die, struct 
> dwarf2_cu *);
> +
>  static const char *namespace_name (struct die_info *die,
>                     int *is_anonymous, struct dwarf2_cu *);
> 
> @@ -2880,14 +2882,12 @@ process_die (struct die_info *die, struct 
> dwarf2_cu *cu)
>        break;
>      case DW_TAG_imported_declaration:
>      case DW_TAG_imported_module:
> -      /* FIXME: carlton/2002-10-16: Eventually, we should use the
> -     information contained in these.  DW_TAG_imported_declaration
> -     dies shouldn't have children; DW_TAG_imported_module dies
> -     shouldn't in the C++ case, but conceivably could in the
> -     Fortran case.  */
>        processing_has_namespace_info = 1;
> -      complaint (&symfile_complaints, _("unsupported tag: '%s'"),
> -         dwarf_tag_name (die->tag));
> +      if (die->child != NULL && (die->tag == DW_TAG_imported_declaration
> +                 || cu->language != language_fortran))
> +    complaint (&symfile_complaints, _("Tag '%s' has unexpected children"),
> +           dwarf_tag_name (die->tag));
> +      read_import_statement (die, cu);
>        break;
>      default:
>        new_symbol (die, NULL, cu);
> @@ -2933,6 +2933,38 @@ dwarf2_full_name (struct die_info *die, struct 
> dwarf2_cu *cu)
>    return name;
>  }
> 
> +/* Read the import statement specified by the given die and record it.  */
> +
> +static void
> +read_import_statement (struct die_info *die, struct dwarf2_cu *cu)
> +{
> +  struct attribute *import_attr;
> +  struct die_info *imported_die;
> +  const char *imported_name;
> +  int is_anonymous = 0;
> +
> +  import_attr = dwarf2_attr (die, DW_AT_import, cu);
> +  if (import_attr == NULL)
> +    {
> +      complaint (&symfile_complaints, _("Tag '%s' has no DW_AT_import"),
> +         dwarf_tag_name (die->tag));
> +      return;
> +    }
> +
> +  imported_die = follow_die_ref (die, import_attr, &cu);
> +  imported_name = namespace_name (imported_die, &is_anonymous, cu);
> +  if (imported_name == NULL)
> +    {
> +      /* C++ imports from std:: DW_TAG_base_type with no DW_AT_name - 
> why?  */
> +      return;
> +    }
> +
> +  /* FIXME: dwarf2_name (die); for the local name after import.  */
> +
> +  using_directives = cp_add_using (imported_name, strlen 
> (imported_name), 0,
> +                                   using_directives);
> +}
> +
>  static void
>  initialize_cu_func_list (struct dwarf2_cu *cu)
>  {
> @@ -3266,6 +3298,7 @@ read_func_scope (struct die_info *die, struct 
> dwarf2_cu *cu)
>       back to building a containing block's symbol lists.  */
>    local_symbols = new->locals;
>    param_symbols = new->params;
> +  using_directives = new->using_directives;
> 
>    /* If we've finished processing a top-level function, subsequent
>       symbols go in the file symbol list.  */
> @@ -3328,6 +3361,7 @@ read_lexical_block_scope (struct die_info *die, 
> struct dwarf2_cu *cu)
>        dwarf2_record_block_ranges (die, block, baseaddr, cu);
>      }
>    local_symbols = new->locals;
> +  using_directives = new->using_directives;
>  }
> 
>  /* Get low and high pc attributes from DW_AT_ranges attribute value 
> OFFSET.
> diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
> index 70ded08..4b34527 100644
> --- a/gdb/testsuite/ChangeLog
> +++ b/gdb/testsuite/ChangeLog
> @@ -1,3 +1,8 @@
> +2009-05-21  Sami Wagiaalla  <swagiaal@redhat.com>
> +
> +    * gdb.cp/namespace-using.exp: New test.
> +    * gdb.cp/namespace-using.cc: New test program.
> +
>  2009-05-18  Jon Beniston <jon@beniston.com>
> 
>          * gdb.asm/asm-source.exp: Add lm32 target.
> diff --git a/gdb/testsuite/gdb.cp/namespace-using.cc 
> b/gdb/testsuite/gdb.cp/namespace-using.cc
> new file mode 100644
> index 0000000..4786fd5
> --- /dev/null
> +++ b/gdb/testsuite/gdb.cp/namespace-using.cc
> @@ -0,0 +1,45 @@
> +namespace A
> +{
> +  int _a = 1;
> +  int x = 2;
> +}
> +
> +int marker4(){
> +    using A::x;
> +    return 0;
> +}
> +
> +int marker3(){
> +    return marker4();
> +}
> +
> +int marker2()
> +{
> +  namespace B = A;
> +  B::_a;
> +  return marker3();
> +}
> +
> +int marker1()
> +{
> +  int total = 0;
> +  {
> +    int b = 1;
> +    {
> +      using namespace A;
> +      int c = 2;
> +      {
> +        int d = 3;
> +        total = _a + b + c + d + marker2(); // marker1 stop
> +      }
> +    }
> +  }
> +  return total;
> +}
> +
> +int main()
> +{
> +  using namespace A;
> +  _a;
> +  return marker1();
> +}
> diff --git a/gdb/testsuite/gdb.cp/namespace-using.exp 
> b/gdb/testsuite/gdb.cp/namespace-using.exp
> new file mode 100644
> index 0000000..2e57927
> --- /dev/null
> +++ b/gdb/testsuite/gdb.cp/namespace-using.exp
> @@ -0,0 +1,87 @@
> +# Copyright 2008 Free Software Foundation, Inc.
> +
> +# This program is free software; you can redistribute it and/or modify
> +# it under the terms of the GNU General Public License as published by
> +# the Free Software Foundation; either version 3 of the License, or
> +# (at your option) any later version.
> +#
> +# This program is distributed in the hope that it will be useful,
> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +# GNU General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License
> +# along with this program.  If not, see <http://www.gnu.org/licenses/>.
> +
> +if $tracelevel then {
> +    strace $tracelevel
> +}
> +
> +set prms_id 0
> +set bug_id 0
> +
> +set testfile namespace-using
> +set srcfile ${testfile}.cc
> +set binfile ${objdir}/${subdir}/${testfile}
> +if  { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" 
> executable {debug c++}] != "" } {
> +    untested "Couldn't compile test program"
> +    return -1
> +}
> +
> +# Get things started.
> +
> +gdb_exit
> +gdb_start
> +gdb_reinitialize_dir $srcdir/$subdir
> +gdb_load ${binfile}
> +
> +############################################
> +# test printing of namespace imported within
> +# the function.
> +
> +if ![runto_main] then {
> +    perror "couldn't run to breakpoint main"
> +    continue
> +}
> +
> +gdb_test "print _a" "= 1"
> +
> +############################################
> +# test printing of namespace imported into
> +# a scope containing the pc.
> +
> +gdb_breakpoint [gdb_get_line_number "marker1 stop"]
> +gdb_continue_to_breakpoint "marker1 stop"
> +
> +gdb_test "print _a" "= 1" "print _a in a nested scope"
> +
> +############################################
> +# Test printing of namespace aliases
> +
> +setup_kfail "gdb/7935" "*-*-*"
> +if ![runto marker2] then {
> +    perror "couldn't run to breakpoint marker2"
> +    continue
> +}
> +
> +gdb_test "print B::a" "= 1"
> +
> +############################################
> +# Test that names are not printed when they
> +# are not imported
> +
> +send_gdb "break marker3\n"
> +gdb_continue_to_breakpoint "marker3"
> +
> +gdb_test "print _a" "No symbol \"_a\" in current context." "Print a 
> without import"
> +
> +############################################
> +# Test printing of individually imported elements
> +
> +setup_kfail "gdb/7936" "*-*-*"
> +if ![runto marker4] then {
> +    perror "couldn't run to breakpoint marker2"
> +    continue
> +}
> +
> +gdb_test "print x" "= 2"
>