[Bug c/45815] New: error: '-fsplit-stack' currently only supported on GNU/Linux

[Bug c/45815] New: error: '-fsplit-stack' currently only supported on GNU/Linux

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45815

           Summary: error: '-fsplit-stack' currently only supported on
                    GNU/Linux
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: dominiq@lps.ens.fr
                CC: iant@google.com
              Host: x86_64-apple-darwin10.4.0
            Target: x86_64-apple-darwin10.4.0
             Build: x86_64-apple-darwin10.4.0


On x86_64-apple-darwin10.4.0 at revision 164677 I see several errors in the
test suite of the kind:

[macbook] f90/bug% gcc46 -c /opt/gcc/work/gcc/testsuite/gcc.dg/pr37106-1.c
/opt/gcc/work/gcc/testsuite/gcc.dg/pr37106-1.c:9:1: error: '-fsplit-stack'
currently only supported on GNU/Linux
/opt/gcc/work/gcc/testsuite/gcc.dg/pr37106-1.c:9:1: error: '-fsplit-stack' is
not supported by this compiler configuration

>From where this '-fsplit-stack' is coming?

[Bug c/45815] error: '-fsplit-stack' currently only supported on GNU/Linux

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45815

--- Comment #1 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2010-09-28 10:06:58 UTC ---
Forgot the -v output:

[macbook] f90/bug% gcc46 -c -v /opt/gcc/work/gcc/testsuite/gcc.dg/pr37106-1.c
Using built-in specs.
COLLECT_GCC=gcc46
COLLECT_LTO_WRAPPER=/opt/gcc/gcc4.6w/libexec/gcc/x86_64-apple-darwin10.4.0/4.6.0/lto-wrapper
Target: x86_64-apple-darwin10.4.0
Configured with: ../work/configure --prefix=/opt/gcc/gcc4.6w
--enable-languages=c,c++,fortran,objc,obj-c++,java,lto --with-gmp=/opt/sw64
--with-libiconv-prefix=/opt/sw64 --with-system-zlib --with-cloog=/opt/sw64
--with-quad=/opt/sw64
Thread model: posix
gcc version 4.6.0 20100928 (experimental) [trunk revision 164677p2] (GCC) 
COLLECT_GCC_OPTIONS='-mmacosx-version-min=10.6.4' '-c' '-v' '-mtune=generic'
 /opt/gcc/gcc4.6w/libexec/gcc/x86_64-apple-darwin10.4.0/4.6.0/cc1 -quiet -v
-D__DYNAMIC__ /opt/gcc/work/gcc/testsuite/gcc.dg/pr37106-1.c -fPIC -quiet
-dumpbase pr37106-1.c -mmacosx-version-min=10.6.4 -mtune=generic -auxbase
pr37106-1 -version -o
/var/folders/LW/LW1oufkMGIqlLpjYn45fBU+++TI/-Tmp-//ccx5QAEF.s
GNU C (GCC) version 4.6.0 20100928 (experimental) [trunk revision 164677p2]
(x86_64-apple-darwin10.4.0)
    compiled by GNU C version 4.6.0 20100928 (experimental) [trunk revision
164677p2], GMP version 5.0.1, MPFR version 3.0.0, MPC version 0.8.2
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
ignoring nonexistent directory "/usr/local/include"
ignoring nonexistent directory
"/opt/gcc/gcc4.6w/lib/gcc/x86_64-apple-darwin10.4.0/4.6.0/../../../../x86_64-apple-darwin10.4.0/include"
#include "..." search starts here:
#include <...> search starts here:
 /opt/gcc/gcc4.6w/lib/gcc/x86_64-apple-darwin10.4.0/4.6.0/include
 /opt/gcc/gcc4.6w/include
 /opt/gcc/gcc4.6w/lib/gcc/x86_64-apple-darwin10.4.0/4.6.0/include-fixed
 /usr/include
 /System/Library/Frameworks
 /Library/Frameworks
End of search list.
GNU C (GCC) version 4.6.0 20100928 (experimental) [trunk revision 164677p2]
(x86_64-apple-darwin10.4.0)
    compiled by GNU C version 4.6.0 20100928 (experimental) [trunk revision
164677p2], GMP version 5.0.1, MPFR version 3.0.0, MPC version 0.8.2
GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
Compiler executable checksum: bc8bd9f4043af97e1ce3a30f0eb920c8
/opt/gcc/work/gcc/testsuite/gcc.dg/pr37106-1.c:9:1: error: '-fsplit-stack'
currently only supported on GNU/Linux
/opt/gcc/work/gcc/testsuite/gcc.dg/pr37106-1.c:9:1: error: '-fsplit-stack' is
not supported by this compiler configuration

[Bug target/45815] [4.6 Regression] error: '-fsplit-stack' currently only supported on GNU/Linux

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45815

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|x86_64-apple-darwin10.4.0   |*-darwin10.4.0
          Component|c                           |target
               Host|x86_64-apple-darwin10.4.0   |
   Target Milestone|---                         |4.6.0
            Summary|error: '-fsplit-stack'      |[4.6 Regression] error:
                   |currently only supported on |'-fsplit-stack' currently
                   |GNU/Linux                   |only supported on GNU/Linux
              Build|x86_64-apple-darwin10.4.0   |
           Severity|normal                      |major

[Bug target/45815] [4.6 Regression] error: '-fsplit-stack' currently only supported on GNU/Linux

[ian at airs dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45815

Ian Lance Taylor <ian at airs dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ian at airs dot com

--- Comment #2 from Ian Lance Taylor <ian at airs dot com> 2010-09-28 15:09:07 UTC ---
That shouldn't happen, because flag_split_stack is initialized to -1, and you
should only see that error if flag_split_stack != -1 in decode_options.  Can
you find out what is setting flag_split_stack to a value other than -1?

[Bug target/45815] [4.6 Regression] error: '-fsplit-stack' currently only supported on GNU/Linux

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45815

--- Comment #3 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2010-09-28 15:19:29 UTC ---
> That shouldn't happen, because flag_split_stack is initialized to -1, and you
> should only see that error if flag_split_stack != -1 in decode_options.  Can
> you find out what is setting flag_split_stack to a value other than -1?

In gcc/opts.c at lines 1092-1102, I see

  if (flag_split_stack == -1)
    flag_split_stack = 0;
  else
    {
      if (!targetm.supports_split_stack (true))
        {
          error ("%<-fsplit-stack%> is not supported by "
                 "this compiler configuration");
          flag_split_stack = 0;
        }
    }

[Bug target/45815] [4.6 Regression] error: '-fsplit-stack' currently only supported on GNU/Linux

[howarth at nitro dot med.uc.edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45815

Jack Howarth <howarth at nitro dot med.uc.edu> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |howarth at nitro dot
                   |                            |med.uc.edu

--- Comment #4 from Jack Howarth <howarth at nitro dot med.uc.edu> 2010-09-28 16:20:31 UTC ---
(In reply to comment #3)
> > That shouldn't happen, because flag_split_stack is initialized to -1, and you
> > should only see that error if flag_split_stack != -1 in decode_options.  Can
> > you find out what is setting flag_split_stack to a value other than -1?
> 
> In gcc/opts.c at lines 1092-1102, I see
> 
>   if (flag_split_stack == -1)
>     flag_split_stack = 0;
>   else
>     {
>       if (!targetm.supports_split_stack (true))
>         {
>           error ("%<-fsplit-stack%> is not supported by "
>                  "this compiler configuration");
>           flag_split_stack = 0;
>         }
>     }

I can confirm on x86_64-apple-darwin that the section...

   if (flag_split_stack == -1)
     flag_split_stack = 0;

is being executed during the compilation of /gcc.dg/pr37106-1.c

[Bug target/45815] [4.6 Regression] error: '-fsplit-stack' currently only supported on GNU/Linux

[ian at airs dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45815

--- Comment #5 from Ian Lance Taylor <ian at airs dot com> 2010-09-28 16:32:16 UTC ---
Dominique: yes, but flag_split_stack should be -1 going into that code, so the
effect of that should be to set flag_split_stack to 0.  Can you confirm that
the generated file options.h was correctly regenerated in your build?  It
should contain the lines

/* Set by -fsplit-stack.
   Generate discontiguous stack frames  */
int flag_split_stack = -1;

[Bug target/45815] [4.6 Regression] error: '-fsplit-stack' currently only supported on GNU/Linux

[dominiq at lps dot ens.fr]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45815

--- Comment #6 from Dominique d'Humieres <dominiq at lps dot ens.fr> 2010-09-28 17:01:07 UTC ---
> Dominique: yes, but flag_split_stack should be -1 going into that code, so the
> effect of that should be to set flag_split_stack to 0.  Can you confirm that
> the generated file options.h was correctly regenerated in your build?  It
> should contain the lines
>
> /* Set by -fsplit-stack.
>    Generate discontiguous stack frames  */
> int flag_split_stack = -1;

It does not:

[macbook] gcc/build_w% grep flag_split_stack *gcc/options.h
gcc/options.h:extern int flag_split_stack;
prev-gcc/options.h:extern int flag_split_stack;
stage1-gcc/options.h:extern int flag_split_stack;

[Bug target/45815] [4.6 Regression] error: '-fsplit-stack' currently only supported on GNU/Linux

[ian at airs dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45815

--- Comment #7 from Ian Lance Taylor <ian at airs dot com> 2010-09-28 17:14:04 UTC ---
I'm sorry, I said options.h, but of course I meant options.c.  Can you check
options.c?

[Bug target/45815] [4.6 Regression] error: '-fsplit-stack' currently only supported on GNU/Linux

[ian at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45815

--- Comment #8 from ian at gcc dot gnu.org <ian at gcc dot gnu.org> 2010-09-28 18:22:19 UTC ---
Author: ian
Date: Tue Sep 28 18:22:13 2010
New Revision: 164695

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=164695
Log:
    PR target/45815
    * opts.c (decode_options): Don't test whether the target supports
    split stack if flag_split_stack == 0.

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

[Bug target/45815] [4.6 Regression] error: '-fsplit-stack' currently only supported on GNU/Linux

[ian at airs dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45815

Ian Lance Taylor <ian at airs dot com> changed:

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

--- Comment #9 from Ian Lance Taylor <ian at airs dot com> 2010-09-28 18:27:15 UTC ---
Should be fixed now.  Thanks for the bug report.