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: 2013-11-19 00:09:39

On 11/18/2013 11:08 PM, Gavin Lambert wrote:
> On 19/11/2013 16:48, Quoth Edward Diener:
>> There are 4 lines of C++FLAGS
>>
>>      toolset.flags msvc.compile C++FLAGS
>> <exception-handling>on/<asynch-exceptions>off/<extern-c-nothrow>off :
>> /EHs ;
>>      toolset.flags msvc.compile C++FLAGS
>> <exception-handling>on/<asynch-exceptions>off/<extern-c-nothrow>on :
>> /EHsc ;
>>      toolset.flags msvc.compile C++FLAGS
>> <exception-handling>on/<asynch-exceptions>on/<extern-c-nothrow>off :
>> /EHa ;
>>      toolset.flags msvc.compile C++FLAGS
>> <exception-handling>on/<asynch-exceptions>on/<extern-c-nothrow>on :
>> /EHac ;
>>
>> How is a particular one chosen ?
>
> I've never really looked into it, but it's pretty clear from the above
> that it will select whichever line matches the AND-combination of the
> settings on that line.  So eg. you'll get /EHs if exception-handling=on
> and asynch-exceptions=off and extern-c-nothrow=off.
>
> As for those settings, they'll either be defined in project-config.jam
> or one of the library, compiler, or builtin jam files.  (Presumably
> searched in that order.)  But that's just a guess.

I am not setting qany options myself and yet plenty of them are part of 
the command line. So i just want to understandf what jam file is 
generating them for the command line.