[Bug other/31353] New: gcc --help=target gives a linker error.

[Bug other/31353] New: gcc --help=target gives a linker error.

[brooks at gcc dot gnu dot org]

Consider the following output:

------------------------------------------------
> ~/bin-trunk/bin/gcc --help=target
The following options are target specific:
  -m128bit-long-double        sizeof(long double) is 16
  -m32                        Generate 32bit i386 code
[...]
  -muclibc                    Use uClibc instead of GNU libc

/usr/lib/crt1.o(.text+0x18): In function `_start':
../sysdeps/i386/elf/start.S:98: undefined reference to `main'
collect2: ld returned 1 exit status
------------------------------------------------

This happens with any --help= option.

It looks like the "--help=" option isn't turning off the parts of the compiler
that do compilation, and so it's still trying to link an empty program.


-- 
           Summary: gcc --help=target gives a linker error.
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: other
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: brooks at gcc dot gnu dot org
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31353

[Bug driver/31353] gcc --help=target gives a linker error.

[pinskia at gcc dot gnu dot org]

------- Comment #1 from pinskia at gcc dot gnu dot org  2007-03-26 00:33 -------
Confirmed.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |nickc at redhat dot com
             Status|UNCONFIRMED                 |NEW
          Component|other                       |driver
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2007-03-25 23:33:06
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31353

[Bug driver/31353] gcc --help=target gives a linker error.

[brooks at gcc dot gnu dot org]

-- 

brooks at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |brooks at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2007-03-25 23:33:06         |2007-03-26 00:21:14
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31353

[Bug driver/31353] gcc --help=target gives a linker error.

[nickc at redhat dot com]

------- Comment #2 from nickc at redhat dot com  2007-03-28 11:38 -------
Subject: Re:  gcc --help=target gives a linker error.

Hi Brooks,

   I have a patch to fix this problem (attached).  Unfortunately due to 
an internal bugzilla error I cannot (currently) upload the patch to this PR.

Cheers
   Nick

gcc/ChangeLog
2007-03-28  Nick Clifton  <nickc@redhat.com>

        PR driver/31353
        * gcc.c (process_command): Pass --help= switch on to
        pre-processor, assembler and linker sub-processes.


Index: gcc/gcc.c
===================================================================
--- gcc/gcc.c   (revision 123290)
+++ gcc/gcc.c   (working copy)
@@ -3607,11 +3607,26 @@ warranty; not even for MERCHANTABILITY o
       else if (strncmp (argv[i], "-fhelp=", 7) == 0)
        {
          /* translate_options () has turned --help into -fhelp.  */
-         print_subprocess_help = 2;
+         print_subprocess_help = 1;

          /* We will be passing a dummy file on to the sub-processes.  */
          n_infiles++;
          n_switches++;
+
+         if (strcmp (argv[i] + 7, "target") == 0)
+           {
+             if (is_cpp_driver)
+               add_preprocessor_option ("--target-help", 13);
+             add_assembler_option ("--target-help", 13);
+             add_linker_option ("--target-help", 13);
+           }
+         else
+           {
+             if (is_cpp_driver)
+               add_preprocessor_option ("--help", 6);
+             add_assembler_option ("--help", 6);
+             add_linker_option ("--help", 6);
+           }
        }
       else if (strcmp (argv[i], "-ftarget-help") == 0)
        {


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31353

[Bug driver/31353] gcc --help=target gives a linker error.

[brooks at gcc dot gnu dot org]

------- Comment #3 from brooks at gcc dot gnu dot org  2007-03-28 19:17 -------
I had previously posted a patch to fix this, as well, but apparently the patch
tracker didn't pick up on it to attach it to the PR:

http://gcc.gnu.org/ml/gcc-patches/2007-03/msg01658.html

As mentioned on the patches list, I don't think that passing --help along to
the subprocesses is the right thing to do here.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31353

[Bug driver/31353] gcc --help=target gives a linker error.

[nickc at redhat dot com]

------- Comment #4 from nickc at redhat dot com  2007-03-29 11:05 -------
Brooks' patch is better than mine, so I would recommend that it be adopted.

Cheers
  Nick


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31353

[Bug driver/31353] gcc --help=target gives a linker error.

[brooks at gcc dot gnu dot org]

------- Comment #5 from brooks at gcc dot gnu dot org  2007-04-04 19:10 -------
Subject: Bug 31353

Author: brooks
Date: Wed Apr  4 19:10:17 2007
New Revision: 123498

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=123498
Log:
PR other/31353
* gcc.c (main): Do not run the linker if
print_subprocess_help indicates that it shouldn't be
run.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/gcc.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31353

[Bug driver/31353] gcc --help=target gives a linker error.

[brooks at gcc dot gnu dot org]

------- Comment #6 from brooks at gcc dot gnu dot org  2007-04-04 19:24 -------
Fixed, as per the above commit.


-- 

brooks at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31353