[Bug driver/47547] New: WHOPR, can't use /dev/null as an output file

[Bug driver/47547] New: WHOPR, can't use /dev/null as an output file

[d.g.gorbachev at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47547

           Summary: WHOPR, can't use /dev/null as an output file
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: trivial
          Priority: P3
         Component: driver
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: d.g.gorbachev@gmail.com


$ touch empty.c
$ gcc -flto empty.c -o /dev/null
lto1: fatal error: can't open /dev/null.s for writing: Permission denied
[...]

[Bug driver/47547] WHOPR, can't use /dev/null as an output file

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47547

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011.01.31 13:29:28
                 CC|                            |hjl at gcc dot gnu.org
     Ever Confirmed|0                           |1

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-01-31 13:29:28 UTC ---
We end up with -dumpdir /dev/ -dumpbase null.wpa.  The failure occurs in

(gdb) up
#1  0x0000000000936029 in init_asm_output (name=0x1780640 "t.o")
    at /space/rguenther/src/svn/trunk/gcc/toplev.c:928
928             fatal_error ("can%'t open %s for writing: %m", asm_file_name);
(gdb) l
923           if (!strcmp (asm_file_name, "-"))
924             asm_out_file = stdout;
925           else
926             asm_out_file = fopen (asm_file_name, "w+b");
927           if (asm_out_file == 0)
928             fatal_error ("can%'t open %s for writing: %m", asm_file_name);
929         }
930
931       if (!flag_syntax_only)
932         {

and

(gdb) p global_options->x_dump_base_name 
$2 = 0x179ce30 "/dev/null.wpa"

I think HJ caused this (the -dumpdir / -dumpbase flags are bogus), non-LTO
does not use -dumpdir, lto-wrapper.c is what sets that flag (I don't
remember why -dumpdir is used at all - HJ?).

Same problem with

gcc -S t.c -o /dev/null -fdump-tree-optimized

btw, so not really LTO specific (but more annoying).

[Bug driver/47547] WHOPR, can't use /dev/null as an output file

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47547

--- Comment #2 from H.J. Lu <hjl.tools at gmail dot com> 2011-01-31 14:32:34 UTC ---
(In reply to comment #1)
> 
> I think HJ caused this (the -dumpdir / -dumpbase flags are bogus), non-LTO
> does not use -dumpdir, lto-wrapper.c is what sets that flag (I don't
> remember why -dumpdir is used at all - HJ?).

It is for PR 41564.

[Bug driver/47547] WHOPR, can't use /dev/null as an output file

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47547

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot       |hjl.tools at gmail dot com
                   |gnu.org                     |

--- Comment #3 from H.J. Lu <hjl.tools at gmail dot com> 2011-01-31 17:00:38 UTC ---
Created attachment 23182
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=23182
A patch

How about this patch?

[Bug driver/47547] WHOPR, can't use /dev/null as an output file

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47547

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.6.0

[Bug driver/47547] [4.5/4.6 Regression] WHOPR, can't use /dev/null as an output file

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47547

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                URL|                            |http://gcc.gnu.org/ml/gcc-p
                   |                            |atches/2011-01/msg02329.htm
                   |                            |l
            Summary|WHOPR, can't use /dev/null  |[4.5/4.6 Regression] WHOPR,
                   |as an output file           |can't use /dev/null as an
                   |                            |output file

--- Comment #4 from H.J. Lu <hjl.tools at gmail dot com> 2011-01-31 19:04:12 UTC ---
A patch is posted at

http://gcc.gnu.org/ml/gcc-patches/2011-01/msg02329.html

[Bug driver/47547] [4.5/4.6 Regression] WHOPR, can't use /dev/null as an output file

[hjl at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47547

--- Comment #5 from hjl at gcc dot gnu.org <hjl at gcc dot gnu.org> 2011-02-01 14:42:16 UTC ---
Author: hjl
Date: Tue Feb  1 14:42:08 2011
New Revision: 169479

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=169479
Log:
Check HOST_BIT_BUCKET when settting dump base/dir.

2011-02-01  H.J. Lu  <hongjiu.lu@intel.com>

    PR driver/47547
    * lto-wrapper.c (run_gcc): Don't add -dumpdir if linker_output
    is HOST_BIT_BUCKET.

    * opts.c (finish_options): Don't add x_aux_base_name if it is
    HOST_BIT_BUCKET.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/lto-wrapper.c
    trunk/gcc/opts.c

[Bug driver/47547] [4.5 Regression] WHOPR, can't use /dev/null as an output file

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47547

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|4.6.0                       |4.5.3
            Summary|[4.5/4.6 Regression] WHOPR, |[4.5 Regression] WHOPR,
                   |can't use /dev/null as an   |can't use /dev/null as an
                   |output file                 |output file

--- Comment #6 from H.J. Lu <hjl.tools at gmail dot com> 2011-02-01 14:43:48 UTC ---
Fixed on trunk.

[Bug driver/47547] [4.5 Regression] WHOPR, can't use /dev/null as an output file

[dnovillo at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47547

--- Comment #7 from Diego Novillo <dnovillo at gcc dot gnu.org> 2011-02-02 18:15:29 UTC ---
Author: dnovillo
Date: Wed Feb  2 18:15:22 2011
New Revision: 169745

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=169745
Log:
Check HOST_BIT_BUCKET when settting dump base/dir.

2011-02-01  H.J. Lu  <hongjiu.lu@intel.com>

    PR driver/47547
    * lto-wrapper.c (run_gcc): Don't add -dumpdir if linker_output
    is HOST_BIT_BUCKET.

    * opts.c (finish_options): Don't add x_aux_base_name if it is
    HOST_BIT_BUCKET.

Modified:
    branches/google/integration/gcc/ChangeLog
    branches/google/integration/gcc/lto-wrapper.c
    branches/google/integration/gcc/opts.c

[Bug driver/47547] [4.5 Regression] WHOPR, can't use /dev/null as an output file

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47547

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P2

[Bug driver/47547] [4.5 Regression] WHOPR, can't use /dev/null as an output file

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47547

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|4.5.3                       |4.6.0

--- Comment #8 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-04-10 10:16:13 UTC ---
Fixed for 4.6.