Re: [PATCH] Algol68: do not clobber A68FLAGS in AC_PROG_A68

> "Jose E. Marchesi" <[email protected]> writes:
>
>> [Sam James found this issue while packaging godcc for Gentoo:
>>  https://packages.gentoo.org/packages/dev-util/godcc.  Would be nice if
>>  we could have this fixed in autoconf 2.73.]
>>
>> The AC_PROG_A68 macro should honor the A68FLAGS set by the user at
>> configure time.
>>
>> Note that a similar fix may be needed in AC_PROG_GO.  I have not fixed
>> that one because it may be intentional there? (unlikely, but just in
>> case.)
>>
>> Signed-off-by: Jose E. Marchesi <[email protected]>
>>
>> 	* lib/autoconf/a68.m4: Do not clobber A68FLAGS in AC_PROG_A68.
>> ---
>>  lib/autoconf/a68.m4 | 10 ++++++++--
>>  1 file changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/lib/autoconf/a68.m4 b/lib/autoconf/a68.m4
>> index 96aee3fc..462199a3 100644
>> --- a/lib/autoconf/a68.m4
>> +++ b/lib/autoconf/a68.m4
>> @@ -124,7 +124,9 @@ AC_DEFUN([AC_LANG_COMPILER(Algol 68)],
>>  AN_MAKEVAR([A68], [AC_PROG_A68])
>>  AN_PROGRAM([ga68], [AC_PROG_A68])
>>  AC_DEFUN([AC_PROG_A68],
>> -[AC_LANG_PUSH(Algol 68)dnl
>> +[ ac_test_A68FLAGS=${A68FLAGS+y}
>> +ac_save_A68FLAGS=$A68FLAGS
>> +AC_LANG_PUSH(Algol 68)dnl
>>  AC_ARG_VAR([A68], [Algol 68 compiler command])dnl
>>  AC_ARG_VAR([A68FLAGS], [Algol 68 compiler flags])dnl
>>  _AC_ARG_VAR_LDFLAGS()dnl
>> @@ -148,6 +150,10 @@ ac_compiler=$[2]
>>  _AC_DO_LIMIT([$ac_compiler --version >&AS_MESSAGE_LOG_FD])
>>  m4_expand_once([_AC_COMPILER_EXEEXT])[]dnl
>>  m4_expand_once([_AC_COMPILER_OBJEXT])[]dnl
>> -A68FLAGS="-g -O2"
>> +if test $ac_test_A68FLAGS; then
>
> Note that this may fail wrongly:
>
>   ~$ ac_test_A68FLAGS='-e 123'
>   ~$ test $ac_test_A68FLAGS || echo fail
>   fail
>
> Probably, what you want is: test x"$ac_test_A68FLAGS" != x
>
> See (autoconf)Limitations of Builtins

Note:

  ac_test_A68FLAGS=${A68FLAGS+y}

which makes the variable to be "y" if A68FLAGS is defined.
  

>> +  A68FLAGS=$ac_save_A68FLAGS
>> +else
>> +  A68FLAGS="-g -O2"
>> +fi
>>  AC_LANG_POP(Algol 68)dnl
>>  ])# AC_PROG_A68