Re: [boost] Strict or lax build configuration

Subject: Re: [boost] Strict or lax build configuration
From: Vladimir Prus (vladimir_at_[hidden])
Date: 2009-11-16 07:21:36

Paul A. Bristow wrote:

>> -----Original Message-----
>> From: boost-bounces_at_[hidden] [mailto:boost-bounces_at_[hidden]] On
> Behalf Of
>> Vladimir Prus
>> Sent: Monday, November 16, 2009 9:57 AM
>> To: boost_at_[hidden]
>> Subject: [boost] Strict or lax build configuration
>> 
>> I have a question how building Boost should behave when the user
>> provides wrong configuration information. E.g., suppose you have this in
>> user-config.jam:
>> 
>> using python : 3.20 : /nowhere ;
>> 
>> or alternatively, in 1.42 a user runs Boost.Build as follows:
>> 
>> ./bjam -sZLIB_INCLUDES=/still-nowhere ...
>> 
>> What should happen?
>> 
>> - A hard error. After all, the user wanted that specific configuration. And
>> warnings are easy to miss.
>> - A warning. Autodetection will still run and possibly find a random version
>> - A hard error, but also run autodetection and let user know what was found.
>>   For example:
>> 
>>       Could not find Python version 3.20 in /nowhere.
>>       There is a valid installation of 2.5 in /usr.
>>       Remove the 'using python' statement to use it.
> 
>  - A hard error, but also run autodetection and let user know what was found.
> 
>        Could not find Python version 3.20 in /somewhere.
>        There is a valid installation of 2.5 in /usr.
>        Remove the 'using python' version to use Python version 2.5 in /usr
>        or install Python version 3.20 at /somewhere.

This wording is indeed better. Thanks.

> (Remove the 'using python' statement means you don't want Python at all?)

If there's no explicit 'using python' then we'll try to find, and use some,
and if there's none, Boost.Python will be skipped, without hard error.

- Volodya