[Bug other/114191] New: Flags "Warning" and "Target" don't mix well in target.opt files

[Bug other/114191] New: Flags "Warning" and "Target" don't mix well in target.opt files

[gjl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114191

            Bug ID: 114191
           Summary: Flags "Warning" and "Target" don't mix well in
                    target.opt files
           Product: gcc
           Version: 13.2.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: other
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gjl at gcc dot gnu.org
  Target Milestone: ---

In an .opt file, a backend can define target-specific diagnostic options, for
example gcc/config/avr/avr.opt has:

Wmisspelled-isr
Warning C C++ Var(avr_warn_misspelled_isr) Init(1)
Warn if the ISR is misspelled, ...

This is a "Target" option however (so it should be listed with --help=target,
which it currently is not). However, specifying the "Target" flag in avr.opt
makes the option no more recognizable:

$ avr-gcc main.c -c -Wall -Wmisspelled-isr
cc1: error: unrecognized command-line option '-Wmisspelled-isr'

I can reproduce this for target avr, but it likely affects all other targets as
well.

Set the component to "other". As it appears, there is no bugzilla component for
such internal problems.

[Bug other/114191] Flags "Warning" and "Target" don't mix well in target.opt files

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114191

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |internal-improvement
                 CC|                            |rguenth at gcc dot gnu.org

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
I think there's no way to mark Warning options as target specific, 'Target'
isn't a flag, it's the main keyword.

How did you specify 'Target'?  I think that

Wmisspelled-isr
Target C C++ Var(avr_warn_misspelled_isr) Init(1)
Warn if the ISR is misspelled, ...

should eventually work?

[Bug other/114191] Flags "Warning" and "Target" don't mix well in target.opt files

[gjl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114191

--- Comment #2 from Georg-Johann Lay <gjl at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #1)
> Wmisspelled-isr
> Target C C++ Var(avr_warn_misspelled_isr) Init(1)
> Warn if the ISR is misspelled, ...
> 
> should eventually work?

With that, the warnings appear as they should, but the option is not
recognized:

$ avr-gcc signal.c -S -Wmisspelled-isr
error: unrecognized command-line option '-Wmisspelled-isr'

$ avr-gcc signal.c -S -Wno-misspelled-isr
error: unrecognized command-line option '-Wno-misspelled-isr'

$ avr-gcc signal.c -S -Werror=misspelled-isr
error: '-Werror=misspelled-isr': '-Wmisspelled-isr' is not an option that
controls warnings

[Bug other/114191] Flags "Warning" and "Target" don't mix well in target.opt files

[gjl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114191

--- Comment #3 from Georg-Johann Lay <gjl at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #1)
> How did you specify 'Target'?

Like:

Wmisspelled-isr
Target Warning C C++ Var(avr_warn_misspelled_isr) Init(1)
Warn if the ISR is misspelled, ...

[Bug other/114191] Flags "Warning" and "Target" don't mix well in target.opt files

[rguenther at suse dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114191

--- Comment #4 from rguenther at suse dot de <rguenther at suse dot de> ---
On Mon, 4 Mar 2024, gjl at gcc dot gnu.org wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114191
> 
> --- Comment #2 from Georg-Johann Lay <gjl at gcc dot gnu.org> ---
> (In reply to Richard Biener from comment #1)
> > Wmisspelled-isr
> > Target C C++ Var(avr_warn_misspelled_isr) Init(1)
> > Warn if the ISR is misspelled, ...
> > 
> > should eventually work?
> 
> With that, the warnings appear as they should, but the option is not
> recognized:
> 
> $ avr-gcc signal.c -S -Wmisspelled-isr
> error: unrecognized command-line option '-Wmisspelled-isr'
> 
> $ avr-gcc signal.c -S -Wno-misspelled-isr
> error: unrecognized command-line option '-Wno-misspelled-isr'
> 
> $ avr-gcc signal.c -S -Werror=misspelled-isr
> error: '-Werror=misspelled-isr': '-Wmisspelled-isr' is not an option that
> controls warnings

Hmm.  This is how some other targets do it, grepping

grep ^W config/*/*.opt

(a bit noisy because of descriptions).

config/gcn/gcn.opt:Wopenacc-dims
config/gcn/gcn.opt:Warn about invalid OpenACC dimensions.
config/i386/mingw.opt:Wpedantic-ms-format
config/i386/mingw.opt:Warn about none ISO msvcrt scanf/printf width 
extensions.

would be not Target but

config/rs6000/darwin.opt:Waltivec-long-deprecated

uses Target (and thus is dysfunctional)

So it seems we're not set up for 'Target' warnings.