[Bug other/54324] New: GCC install document does not list minimum required g++ versions

[Bug other/54324] New: GCC install document does not list minimum required g++ versions

[gary at intrepid dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

             Bug #: 54324
           Summary: GCC install document does not list minimum required
                    g++ versions
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: other
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: gary@intrepid.com


Ref: http://gcc.gnu.org/ml/gcc-patches/2012-08/msg01223.html

Currently, install.texi states:

    @heading Tools/packages necessary for building GCC
    @table @asis
    @item ISO C90 compiler
    Necessary to bootstrap GCC, although versions of GCC prior
    to 3.4 also allow bootstrapping with a traditional (K&R) C compiler.

    To build all languages in a cross-compiler or other configuration where
    3-stage bootstrap is not performed, you need to start with an existing
    GCC binary (version 2.95 or later) because source code for language
    frontends other than C might use GCC extensions.

This appears to be out-of-date with respect to new GCC 4.8 C++ stage 1
build requirement.

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |documentation
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-08-20
   Target Milestone|---                         |4.8.0
            Summary|GCC install document does   |[4.8 Regression] GCC
                   |not list minimum required   |install document does not
                   |g++ version                 |list minimum required g++
                   |                            |version
     Ever Confirmed|0                           |1

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-08-20 07:18:51 UTC ---
Confirmed.  Marked as regression to be on the radar.

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |blocker

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[aldyh at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

Aldy Hernandez <aldyh at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |aldyh at gcc dot gnu.org
         AssignedTo|unassigned at gcc dot       |aldyh at gcc dot gnu.org
                   |gnu.org                     |

--- Comment #2 from Aldy Hernandez <aldyh at gcc dot gnu.org> 2012-12-10 18:11:13 UTC ---
I'll investigate a bit further.

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[aldyh at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

--- Comment #3 from Aldy Hernandez <aldyh at gcc dot gnu.org> 2012-12-10 19:40:17 UTC ---
I was successfully able to bootstrap trunk with a freshly built 3.4.0 compiler:

houston:/build/trunk$ gcc -v
Reading specs from
/home/build/old-gccs/3.4.0/install/bin/../lib/gcc/x86_64-unknown-linux-gnu/3.4.0/specs
Configured with: /source/old-gccs/gcc-3.4.0/configure --enable-languages=c,c++
Thread model: posix
gcc version 3.4.0

This was on an x86-64 Linux running Fedora release 17.

The original bug report in the mailing list post was against an x86-32 Linux
(Redhat 8.0) system, which is different, but perhaps this is something else
(not the compiler)??

I will investigate on a Red Hat 8.0 system.

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> 2012-12-11 10:13:10 UTC ---
I am preparing a first patch, we of course need to verify the assertions in it
are true ;)

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> 2012-12-11 10:19:32 UTC ---
Author: rguenth
Date: Tue Dec 11 10:19:21 2012
New Revision: 194389

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=194389
Log:
2012-12-11  Richard Biener  <rguenther@suse.de>

    PR other/54324
    * doc/install.texi (Tools/packages necessary for building GCC):
    State ISO C++98 host compiler requirement.  Increment minimum
    GCC version required for building all languages for a cross-compiler
    to 3.4 or later.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/doc/install.texi

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

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

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

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> 2012-12-11 10:20:28 UTC ---
Fixed as far as I am concerned.

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[aldyh at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

--- Comment #7 from Aldy Hernandez <aldyh at gcc dot gnu.org> 2012-12-12 05:09:09 UTC ---
Another proposed patch.
http://gcc.gnu.org/ml/gcc-patches/2012-12/msg00766.html

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-12-12 10:56:40 UTC ---
(In reply to comment #7)
> Another proposed patch.
> http://gcc.gnu.org/ml/gcc-patches/2012-12/msg00766.html

I very strongly second what stevenb said:

  GCC 3.2 claims many things, but any GCC that has the old C++ parser
  has known non-conformances. IMHO we should only support GCC versions
  with the "new" C++ parser, i.e. GCC 3.4 and up.

Expecting people to bootstap with GCC 3.2 to check it doesn't barf on some
perfectly valid piece of C++ is unreasonable.  If people didn't bootstrap with
3.2 then incompatibilities would creep in and not be found, so claiming that
using 3.2 is possible would be a lie.  Just say no.

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[aldyh at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

--- Comment #9 from Aldy Hernandez <aldyh at gcc dot gnu.org> 2012-12-18 15:19:55 UTC ---
Author: aldyh
Date: Tue Dec 18 15:19:43 2012
New Revision: 194583

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=194583
Log:
    PR other/54324
    * ansidecl.h (ATTRIBUTE_UNUSED): Do not set __attribute__ for GCC
    < 3.4.

Modified:
    trunk/include/ChangeLog
    trunk/include/ansidecl.h

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[aldyh at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

--- Comment #10 from Aldy Hernandez <aldyh at gcc dot gnu.org> 2012-12-18 15:26:50 UTC ---
Author: aldyh
Date: Tue Dec 18 15:26:27 2012
New Revision: 194584

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=194584
Log:
    PR other/54324
    * tree-ssa-coalesce.c (struct ssa_name_var_hash): Remove "union"
    from template parameter.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/tree-ssa-coalesce.c

[Bug other/54324] [4.8 Regression] GCC install document does not list minimum required g++ version

[aldyh at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54324

--- Comment #11 from Aldy Hernandez <aldyh at gcc dot gnu.org> 2012-12-18 16:22:11 UTC ---
Author: aldyh
Date: Tue Dec 18 16:21:57 2012
New Revision: 194586

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=194586
Log:
    PR other/54324
    * doc/install.texi (Tools/packages necessary for building GCC):
    Suggest --disable-stage1-checking for older GCC's.

Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/doc/install.texi