Re: [boost] [build] Default compiler options for a toolset

Subject: Re: [boost] [build] Default compiler options for a toolset
From: Edward Diener (eldiener_at_[hidden])
Date: 2013-12-08 16:03:44

On 12/5/2013 2:32 AM, Edward Diener wrote:
> On 11/21/2013 2:42 AM, Vladimir Prus wrote:
>> On 21.11.2013 10:16, Edward Diener wrote:
>>> On 11/21/2013 12:30 AM, Vladimir Prus wrote:
>>>> On 21.11.2013 05:42, Edward Diener wrote:
>>>>> On 11/20/2013 6:59 PM, Gavin Lambert wrote:
>>>>>> On 21/11/2013 12:33, Quoth Edward Diener:
>>>>>>> I did not think I was removing them, justy changing them to
>>>>>>> produce no
>>>>>>> compiler option. It seems a flaw in the system that one cannot
>>>>>>> specify
>>>>>>> generating no compiler option for some Boost Build option(s).
>>>>>>> What do
>>>>>>> you do when some compiler has no equivalent compiler option for a
>>>>>>> Boost
>>>>>>> Build option ?
>>>>>>
>>>>>> You don't specify it in the first place.
>>>>>>
>>>>>> The problem you're having is because your jamfile is including the
>>>>>> msvc
>>>>>> jamfile, but the compiler is not 100% msvc compliant.
>>>>>>
>>>>>> Another way you could have done it would have been to copy the msvc
>>>>>> file
>>>>>> and edit it to match the real capabilities of clang-win, instead of
>>>>>> including the msvc file.
>>>>>
>>>>> You may be right about this but someone else created the jam file, not
>>>>> me. I am just trying to modify it. OTOH inheriting flags from msvc
>>>>> seems logically much cleaner than having to duplicate them, or even
>>>>> duplicate almost all of them.
>>>>
>>>> toolset.inherit is defined like this:
>>>>
>>>>      rule inherit ( toolset : base )
>>>>      {
>>>>          import $(base) ;
>>>>          inherit-generators $(toolset) : $(base) ;
>>>>          inherit-flags      $(toolset) : $(base) ;
>>>>          inherit-rules      $(toolset) : $(base) ;
>>>>      }
>>>>
>>>> You probably can do what clang-darwin does - don't call
>>>> toolset.inherit,
>>>> call these 3 functions directly, and then note this
>>>> comment for inherit-flags:
>>>>
>>>>      # Brings all flag definitions from the 'base' toolset into the
>>>> 'toolset'
>>>>      # toolset. Flag definitions whose conditions make use of
>>>> properties in
>>>>      # 'prohibited-properties' are ignored. Do not confuse property and
>>>> feature, for
>>>>      # example <debug-symbols>on and <debug-symbols>off, so blocking
>>>> one
>>>> of them does
>>>>      # not block the other one.
>>>>      #
>>>>      # The flag conditions are not altered at all, so if a condition
>>>> includes a name,
>>>>      # or version of a base toolset, it will not ever match the
>>>> inheriting toolset.
>>>>      # When such flag settings must be inherited, define a rule in base
>>>> toolset
>>>>      # module and call it as needed.
>>>>      #
>>>>      rule inherit-flags ( toolset : base : prohibited-properties * :
>>>> prohibited-vars * )
>>>>
>>>> So, if clang on windows does not have any particular options for
>>>> exception handling you would use:
>>>>
>>>>      toolset.inherit-flags clang-win : msvc : <exception-handling>on ;
>>>>
>>>> or maybe
>>>>
>>>>      toolset.inherit-flags clang-win : msvc : <asynch-exceptions>off
>>>> <asynch-exceptions>on ;
>>>
>>> First of all the toolset was uploaded as an attachment to a message in
>>> the Boost Build mailing list by 'tr1gun' in reply to a message he
>>> started on that list called 'Clang windows toolset.
>>>
>>> The toolset jam file does does have these lines:
>>>
>>> toolset.inherit-generators clang-win <toolset>clang
>>> <toolset-clang:platform>win : msvc ;
>>> toolset.inherit-flags clang-win : msvc :
>>> <debug-symbols>on/<debug-store>object  : YLOPTION ;
>>> toolset.inherit-rules clang-win : msvc ;
>>>
>>> The issue is that clang does not support any /EH(x) option of msvc and
>>> I am trying to change it so that option is not generated when using
>>> the clang-win toolset is used to compile ( clang-cl ).
>>
>> So what if you add
>>
>>      <asynch-exceptions>off <asynch-exceptions>on
>>
>> to inherit-flags invocation above?
>
> That works ! Thanks for the solution to the problem of eliminating
> /EH(x) from the clang using VC++ RTL tests.

I spoke soo soon. Even with the above added to the inherit-flags 
invocation the command line still generates the /EHs option.