[Bug debug/38390] New: Missing DW_TAG_imported_module

[Bug debug/38390] New: Missing DW_TAG_imported_module

[jan dot kratochvil at redhat dot com]

It works on Fedora gcc-c++-4.3.2-7.x86_64 but on 4.4-HEAD DIEs for
DW_TAG_imported_module are just missing.

import.C
------------------------------------------------------------------------------
namespace A
  {
    int v;
  }

int
f ()
{
  using namespace A;
  return v;
}
------------------------------------------------------------------------------

g++ -c -o import.o import.C -Wall -g

>From gcc-c++-4.3.2-7.x86_64:
 <1><2d>: Abbrev Number: 2 (DW_TAG_subprogram)
    <2e>   DW_AT_external    : 1        
    <2f>   DW_AT_name        : f        
    <31>   DW_AT_decl_file   : 1        
    <32>   DW_AT_decl_line   : 7        
    <33>   DW_AT_MIPS_linkage_name: (indirect string, offset: 0x37): _Z1fv      
    <37>   DW_AT_type        : <0x5b>   
    <3b>   DW_AT_low_pc      : 0x0      
    <43>   DW_AT_high_pc     : 0xc      
    <4b>   DW_AT_frame_base  : 0x0      (location list)
    <4f>   DW_AT_sibling     : <0x5b>   
 <2><53>: Abbrev Number: 3 (DW_TAG_imported_module)
    <54>   DW_AT_decl_file   : 1        
    <55>   DW_AT_decl_line   : 9        
    <56>   DW_AT_import      : <0x62>   [Abbrev Number: 5 (DW_TAG_namespace)]

From
GNU C++ (GCC) version 4.4.0 20081202 (experimental) (x86_64-unknown-linux-gnu)
        compiled by GNU C version 4.4.0 20081202 (experimental), GMP version
4.2.2, MPFR version 2.3.2.
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
 <1><2d>: Abbrev Number: 2 (DW_TAG_subprogram)
    <2e>   DW_AT_external    : 1        
    <2f>   DW_AT_name        : f        
    <31>   DW_AT_decl_file   : 1        
    <32>   DW_AT_decl_line   : 7        
    <33>   DW_AT_MIPS_linkage_name: (indirect string, offset: 0x2b): _Z1fv      
    <37>   DW_AT_type        : <0x4f>   
    <3b>   DW_AT_low_pc      : 0x0      
    <43>   DW_AT_high_pc     : 0xc      
    <4b>   DW_AT_frame_base  : 0x0      (location list)

(other DIEs exactly the same, DW_TAG_imported_module is missing here)


-- 
           Summary: Missing DW_TAG_imported_module
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: debug
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jan dot kratochvil at redhat dot com
 GCC build triplet: x86_64-unknown-linux-gnu
  GCC host triplet: x86_64-unknown-linux-gnu
GCC target triplet: x86_64-unknown-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38390

[Bug debug/38390] Missing DW_TAG_imported_module

[dodji at gcc dot gnu dot org]

-- 

dodji at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |dodji at gcc dot gnu dot org
                   |dot org                     |
             Status|UNCONFIRMED                 |ASSIGNED
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2008-12-05 16:17:53
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38390

[Bug debug/38390] Missing DW_TAG_imported_module

[dodji at gcc dot gnu dot org]

------- Comment #1 from dodji at gcc dot gnu dot org  2008-12-05 20:27 -------
It looks like this is due to the fact that f contains no statement considered
"meaningful" by the front end. So, no BIND_EXPR node is being generated for its
body, so no debug info is being generated for its body either.

For instance, in the example below:

namespace A
  {
    int v;
  }

int
f ()
{
  int i = 0;
  using namespace A;
  return v;
}

the DW_AT_imported_module is being generated correctly.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38390

[Bug debug/38390] Missing DW_TAG_imported_module

[dodji at gcc dot gnu dot org]

------- Comment #2 from dodji at gcc dot gnu dot org  2008-12-05 20:29 -------
Created an attachment (id=16834)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=16834&action=view)
A candidate patch

This patch seems to fix the problem. I haven't tried to make it pass regtests
yet though.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38390

[Bug debug/38390] Missing DW_TAG_imported_module

[dodji at gcc dot gnu dot org]

------- Comment #3 from dodji at gcc dot gnu dot org  2008-12-07 22:19 -------
The patch passes regtests. I have posted it to
http://gcc.gnu.org/ml/gcc-patches/2008-12/msg00442.html


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38390

[Bug debug/38390] Missing DW_TAG_imported_module

[dodji at gcc dot gnu dot org]

------- Comment #4 from dodji at gcc dot gnu dot org  2008-12-08 19:02 -------
Subject: Bug 38390

Author: dodji
Date: Mon Dec  8 19:00:46 2008
New Revision: 142562

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=142562
Log:
gcc/cp/ChangeLog:
2008-12-07  Dodji Seketeli  <dodji@redhat.com>

        PR debug/38390
        * name-lookup.c (kept_level_p): Don't forget the case of levels
          having using directives.

gcc/testsuite/ChangeLog:
2008-12-07  Dodji Seketeli  <dodji@redhat.com>

        PR debug/38390
        * g++.dg/debug/dwarf2/imported-module-2.C: New test.


Added:
    trunk/gcc/testsuite/g++.dg/debug/dwarf2/imported-module-2.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/name-lookup.c
    trunk/gcc/testsuite/ChangeLog


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38390

[Bug debug/38390] Missing DW_TAG_imported_module

[dodji at gcc dot gnu dot org]

------- Comment #5 from dodji at gcc dot gnu dot org  2008-12-08 19:25 -------
Fixed in trunk.


-- 

dodji at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38390

[Bug debug/38390] Missing DW_TAG_imported_module

[pinskia at gcc dot gnu dot org]

-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pinskia at gcc dot gnu dot
                   |                            |org
   Target Milestone|---                         |4.4.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38390