[PATCH] configure: Remove --enable-all-warnings option

[Adhemerval Zanella Netto]

On 24/07/23 14:44, Siddhesh Poyarekar wrote:
> On 2023-07-24 13:22, Adhemerval Zanella via Libc-alpha wrote:
>> The option is not activelly tested and has bitrotten, to fix it
>> would require a lot of work and multiple fixes.  A better option
>> would to evaluate each option and enable the warning if it makes
>> sense.
> 
> Can we do that evaluation and then drop this flag?  I feel like a number of them could be added in the default configuration.

I have evaluate some of them, but some are really time consuming (like
Wcast-qual), and others are required in some code (like -Wbad-function-cast).
Some are really not that useful, like -Wcomment/-Wcomments/-Wtrigraphs;
but I think  -Wmissing-prototypes/-Wmissing-declarations might be useful.
I would like to add -Wtrampolines, but it would require to maskoff for
hurd.

I started to work on enable -Wmissing-noreturn, but I did not see much
gain in code generation and it was a quite large patch.

In any case, I still think we should remove the configure regardless
since it is currently unusable. 

> 
> Thanks,
> Sid
> 
>> ---
>>   Makeconfig     |  7 +------
>>   config.make.in |  1 -
>>   configure      | 11 -----------
>>   configure.ac   | 10 ----------
>>   4 files changed, 1 insertion(+), 28 deletions(-)
>>
>> diff --git a/Makeconfig b/Makeconfig
>> index 77d7fd14df..c4dd9ea8f2 100644
>> --- a/Makeconfig
>> +++ b/Makeconfig
>> @@ -857,12 +857,7 @@ host-test-program-cmd = $(host-built-program-cmd)
>>   endif
>>     # Extra flags to pass to GCC.
>> -ifeq ($(all-warnings),yes)
>> -+gccwarn := -Wall -Wwrite-strings -Wcast-qual -Wbad-function-cast -Wmissing-noreturn -Wmissing-prototypes -Wmissing-declarations -Wcomment -Wcomments -Wtrigraphs -Wsign-compare -Wfloat-equal -Wmultichar
>> -else
>> -+gccwarn := -Wall -Wwrite-strings
>> -endif
>> -+gccwarn += -Wundef
>> +gccwarn := -Wall -Wwrite-strings -Wundef
>>   ifeq ($(enable-werror),yes)
>>   +gccwarn += -Werror
>>   endif
>> diff --git a/config.make.in b/config.make.in
>> index d487a4f4e9..0c4baa2731 100644
>> --- a/config.make.in
>> +++ b/config.make.in
>> @@ -50,7 +50,6 @@ c++-sysincludes = @CXX_SYSINCLUDES@
>>   c++-cstdlib-header = @CXX_CSTDLIB_HEADER@
>>   c++-cmath-header = @CXX_CMATH_HEADER@
>>   c++-bits-std_abs-h = @CXX_BITS_STD_ABS_H@
>> -all-warnings = @all_warnings@
>>   enable-werror = @enable_werror@
>>     have-z-execstack = @libc_cv_z_execstack@
>> diff --git a/configure b/configure
>> index 4ef387146d..eeb3ef49b8 100755
>> --- a/configure
>> +++ b/configure
>> @@ -705,7 +705,6 @@ libc_cv_nss_crypt
>>   build_crypt
>>   memory_tagging
>>   enable_werror
>> -all_warnings
>>   force_install
>>   bindnow
>>   hardcoded_path_in_tests
>> @@ -804,7 +803,6 @@ enable_static_nss
>>   enable_force_install
>>   enable_maintainer_mode
>>   enable_kernel
>> -enable_all_warnings
>>   enable_werror
>>   enable_multi_arch
>>   enable_memory_tagging
>> @@ -1478,7 +1476,6 @@ Optional Features:
>>                             sometimes confusing) to the casual installer
>>     --enable-kernel=VERSION compile for compatibility with kernel not older than
>>                             VERSION
>> -  --enable-all-warnings   enable all useful warnings gcc can issue
>>     --disable-werror        do not build with -Werror
>>     --enable-multi-arch     enable single DSO with optimizations for multiple
>>                             architectures
>> @@ -4526,14 +4523,6 @@ else
>>     fi
>>   fi
>>   -# Check whether --enable-all-warnings was given.
>> -if test ${enable_all_warnings+y}
>> -then :
>> -  enableval=$enable_all_warnings; all_warnings=$enableval
>> -fi
>> -
>> -
>> -
>>   # Check whether --enable-werror was given.
>>   if test ${enable_werror+y}
>>   then :
>> diff --git a/configure.ac b/configure.ac
>> index 12d1f50b14..6601331a06 100644
>> --- a/configure.ac
>> +++ b/configure.ac
>> @@ -277,16 +277,6 @@ else
>>     fi
>>   fi
>>   -dnl For the development we sometimes want gcc to issue even more warnings.
>> -dnl This is not the default since many of the extra warnings are not
>> -dnl appropriate.
>> -AC_ARG_ENABLE([all-warnings],
>> -          AS_HELP_STRING([--enable-all-warnings],
>> -                 [enable all useful warnings gcc can issue]),
>> -          [all_warnings=$enableval],
>> -          [])
>> -AC_SUBST(all_warnings)
>> -
>>   AC_ARG_ENABLE([werror],
>>             AS_HELP_STRING([--disable-werror],
>>                    [do not build with -Werror]),