[Bug ada/17540] New: Duplicate symbols while building Ada

[Bug ada/17540] New: Duplicate symbols while building Ada

[laurent at guerby dot net]

Filed to enable tracking, from "Ada system.fat_lflt.fat_long_float.scaling
problem analysis" discussion on gcc@gcc.gnu.org:

On Mon, 2004-09-13 at 23:24, Richard Kenner wrote:
>     s-fatlfl.o(.bss+0x0): In function `system.fat_lflt.fat_long_float.scaling':
>    
/home/guerby/work/gcc/build/build-20040913T200122/gcc/ada/rts/s-fatgen.adb:540:
multiple definition of `r'
>    
s-fatflt.o(.bss+0x0):/home/guerby/work/gcc/build/build-20040913T200122/gcc/ada/rts/s-fatgen.adb:540:
first defined here
> 
> I'm assuming this is a problem in the Ada front end, though I haven't
> gotten a chance to look at it yet.

I looked at the expanded code for s-fatflt.ads and found the "r":

xa : constant system.system__address := 
           system__fat_flt__fat_float__valid__to_addressGP22755__target!
           (system__fat_flt__fat_float__valid__float_access(x));
r : system__fat_flt__fat_float__valid__float_rep;
        pragma import (ada, r);
        for r'address use xa;
        freeze r []

The following reduced test case shows the problem:

procedure P is
   procedure P1 (X : access Integer) is
      R : Integer;
      pragma Import (Ada, R);
      for R'Address use X.all'Address;
   begin
      null;
   end P1;
   procedure P2 (X : access Integer) is
      R : Integer;
      pragma Import (Ada, R);
      for R'Address use X.all'Address;
   begin
      null;
   end P2;
begin
   null;
end P;

$ /home/guerby/work/gcc/build/build-20040917T192720/gcc/xgcc
-B/home/guerby/work/gcc/build/build-20040917T192720/gcc/ -c p.adb
/tmp/ccK6lePn.s: Assembler messages:
/tmp/ccK6lePn.s:13: Error: symbol `r' is already defined

My guess is that the r symbol is not flagged as local when
there's an address clause and an Import pragma, so it
might be a gigi problem.


Very similar code is present in GNAT sources and is causing the ACATS
failures, see s-fatgen.adb, function Valid:

      XA : constant System.Address := To_Address (Float_Access (X));

      R : Float_Rep;
      pragma Import (Ada, R);
      for R'Address use XA;
      --  R is a view of the input floating-point parameter. Note that we
      --  must avoid copying the actual bits of this parameter in float
      --  form (since it may be a signalling NaN.

Since it's a generic, it might lead to generated code
as I've writen in my example if multiple instanciation
are present. Such a construct has worked for all versions of GNAT, but might depend
on some specific code generation behaviour that is no longer present.

-- 
           Summary: Duplicate symbols while building Ada
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: ada
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: laurent at guerby dot net
                CC: dewar at gnat dot com,gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17540

[Bug ada/17540] Duplicate symbols while building Ada

[fw at deneb dot enyo dot de]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |fw at deneb dot enyo dot de


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17540

[Bug ada/17540] Duplicate symbols while building Ada

[charlet at gcc dot gnu dot org]

------- Additional Comments From charlet at gcc dot gnu dot org  2004-09-20 10:51 -------
confirmed.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
   Last reconfirmed|0000-00-00 00:00:00         |2004-09-20 10:51:05
               date|                            |
   Target Milestone|---                         |4.0.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17540

[Bug ada/17540] Duplicate symbols while building Ada

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-09-20 12:08 -------
Subject: Bug 17540

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	charlet@gcc.gnu.org	2004-09-20 12:07:53

Modified files:
	gcc/ada        : freeze.adb ChangeLog 

Log message:
	2004-09-20  Robert Dewar  <dewar@gnat.com>
	
	PR ada/17540
	
	* freeze.adb (Check_Address_Clause): Reset Is_Imported and Is_Public
	if an address clause is present, since that means that the Import
	should be ignored.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ada/freeze.adb.diff?cvsroot=gcc&r1=1.20&r2=1.21
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ada/ChangeLog.diff?cvsroot=gcc&r1=1.563&r2=1.564



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17540

[Bug ada/17540] Duplicate symbols while building Ada

[charlet at gcc dot gnu dot org]

------- Additional Comments From charlet at gcc dot gnu dot org  2004-09-20 12:10 -------
Fixed.

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17540

[Bug ada/17540] Duplicate symbols while building Ada

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-09-23 09:00 -------
Subject: Bug 17540

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	charlet@gcc.gnu.org	2004-09-23 09:00:12

Modified files:
	gcc/ada        : sem_prag.adb freeze.adb ChangeLog 

Log message:
	2004-09-23  Robert Dewar  <dewar@gnat.com>
	
	PR ada/17540
	
	* sem_prag.adb (Process_Import_Or_Interface): Don't set Is_Public here,
	instead do this at freeze time (we won't do it if there is an address
	clause).
	Change "pragma inline" to "pragma Inline" in information and error
	messages.
	Minor reformatting.
	
	* freeze.adb (Check_Address_Clause): Remove previous change, not the
	right way of doing things after all.
	(Freeze_Entity): For object, set Is_Public for imported entities
	unless there is an address clause present.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ada/sem_prag.adb.diff?cvsroot=gcc&r1=1.42&r2=1.43
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ada/freeze.adb.diff?cvsroot=gcc&r1=1.21&r2=1.22
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ada/ChangeLog.diff?cvsroot=gcc&r1=1.567&r2=1.568



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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17540