[Bug c/100909] New: powerpc64le: Regression causing unexpected error with IBM long double

[Bug c/100909] New: powerpc64le: Regression causing unexpected error with IBM long double

[tuliom at ascii dot art.br]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100909

            Bug ID: 100909
           Summary: powerpc64le: Regression causing unexpected error with
                    IBM long double
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: tuliom at ascii dot art.br
  Target Milestone: ---

Created attachment 50934
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50934&action=edit
Pre-processed s_modff128-ifunc.c file from glibc

I've recently started seeing this regression while building glibc on
powerpc64le:

gcc -m64 test.i -c -mlong-double-128   -mabi=ibmlongdouble
/home/tuliom/tmp/at-build-tray/at15.0-0-alpha.suse-15_ppc64le_ppc64le/builds/glibc_1-64/math/s_modff128-ifunc.c:8:1:
error: ‘-mabi=ibmlongdouble’ requires ‘-mlong-double-128’
    8 | DECL_ALIAS_s_modf (modf);
      | ^~~~~~

Notice that both parameters are being passed to GCC.

I've bisected this issue to:

commit ebd5e86c0f41dc1d692f9b2b68a510b1f6835a3e
Author: Martin Liska <mliska@suse.cz>
Date:   Wed Mar 10 15:12:31 2021 +0100

    Improve global state for options.

    gcc/c-family/ChangeLog:

            PR tree-optimization/92860
            PR target/99592
            * c-attribs.c (handle_optimize_attribute): Save target node
            before calling parse_optimize_options and save it in case
            it changes.
            * c-pragma.c (handle_pragma_target): Similarly for pragma.
            (handle_pragma_pop_options): Likewise here.

    gcc/ChangeLog:

            PR tree-optimization/92860
            PR target/99592
            * optc-save-gen.awk: Remove exceptions.


I can still reproduce it with commit ee9548b36a7f.

[Bug target/100909] [12 Regression] powerpc64le: Regression causing unexpected error with IBM long double

[bergner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100909

Peter Bergner <bergner at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
                 CC|                            |bergner at gcc dot gnu.org,
                   |                            |marxin at gcc dot gnu.org,
                   |                            |segher at gcc dot gnu.org
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2021-06-04

--- Comment #1 from Peter Bergner <bergner at gcc dot gnu.org> ---
Confirmed.  creduce on the attached test case gives me:

bergner@pike:~/gcc/BUGS/PR100909$ cat pr100909.i
void __attribute__((__optimize__("O2"))) a() { }

bergner@pike:~/gcc/BUGS/PR100909$
/home/bergner/gcc/build/gcc-fsf-mainline-pr100799-debug/gcc/xgcc
-B/home/bergner/gcc/build/gcc-fsf-mainline-pr100799-debug/gcc -S 
-mlong-double-128 -mabi=ibmlongdouble pr100909.i 
pr100909.i:1:1: error: ‘-mabi=ibmlongdouble’ requires ‘-mlong-double-128’
    1 | void __attribute__((__optimize__("O2"))) a() { }
      | ^~~~
pr100909.i: In function ‘a’:
pr100909.i:1:1: error: ‘-mabi=ibmlongdouble’ requires ‘-mlong-double-128’
pr100909.i:1:1: error: ‘-mabi=ibmlongdouble’ requires ‘-mlong-double-128’
pr100909.i:1:42: error: ‘-mabi=ibmlongdouble’ requires ‘-mlong-double-128’
    1 | void __attribute__((__optimize__("O2"))) a() { }
      |                                          ^
pr100909.i:1:42: error: ‘-mabi=ibmlongdouble’ requires ‘-mlong-double-128’

[Bug target/100909] [12 Regression] powerpc64le: Regression causing unexpected error with IBM long double

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100909

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED

--- Comment #2 from Martin Liška <marxin at gcc dot gnu.org> ---
Mine, I've got a patch for it.

[Bug target/100909] [12 Regression] powerpc64le: Regression causing unexpected error with IBM long double

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100909

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |12.0

[Bug target/100909] [12 Regression] powerpc64le: Regression causing unexpected error with IBM long double

[bergner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100909

--- Comment #3 from Peter Bergner <bergner at gcc dot gnu.org> ---
(In reply to Martin Liška from comment #2)
> Mine, I've got a patch for it.

Hi Martin, any status on how your patch worked out?

[Bug target/100909] [12 Regression] powerpc64le: Regression causing unexpected error with IBM long double

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100909

--- Comment #4 from Martin Liška <marxin at gcc dot gnu.org> ---
> Hi Martin, any status on how your patch worked out?

Hello. Waiting for Segher to reply and I've just pinged that right now.

[Bug target/100909] [12 Regression] powerpc64le: Regression causing unexpected error with IBM long double

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100909

Martin Liška <marxin at gcc dot gnu.org> changed:

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

--- Comment #5 from Martin Liška <marxin at gcc dot gnu.org> ---
It's fixed now since g:318113a961220c8da79d8d29619138827ccc69f1

commit 318113a961220c8da79d8d29619138827ccc69f1
Author: Martin Liska <mliska@suse.cz>
Date:   Tue Jun 1 15:39:14 2021 +0200

    rs6000: Fix restored rs6000_long_double_type_size

    As mentioned in the "Fallout: save/restore target options in
handle_optimize_attribute"
    thread, we need to support target option restore
    of rs6000_long_double_type_size == FLOAT_PRECISION_TFmode.

    gcc/ChangeLog:

            * config/rs6000/rs6000.c (rs6000_option_override_internal): When
            a target option is restored, it can have
            rs6000_long_double_type_size set to FLOAT_PRECISION_TFmode
            and error should not be emitted.

    gcc/testsuite/ChangeLog:

            * gcc.target/powerpc/pragma-optimize.c: New test.