Re: [boost] "Unknown compiler version"

From: vicente.botet (vicente.botet_at_[hidden])
Date: 2008-05-17 04:06:39

---------------------------
Vicente Juan Botet Escriba
----- Original Message ----- 
From: "Vladimir Prus" <vladimir_at_[hidden]>
To: <boost_at_[hidden]>
Sent: Saturday, May 17, 2008 8:29 AM
Subject: [boost] "Unknown compiler version"

>
> Hi,
> quite a number of headers in boost/config/compiler have bits like this:
>
>    #     error "Unknown compiler version - please run the configure tests 
> and report the results"
>
> I think this cause more hard than good these days. If a new version of an 
> otherwise perfectly
> conforming compiler is released, this error will be emitted when compiling 
> Boost. So, users would
> have to manually hack the config headers and keep this change locally. 
> And, it's likely that some
> users won't even bother -- especially given that the message say to run 
> some configure tests,
> and where those configure tests are is not clear. And definitely, those 
> tests have nothing to do
> with the 'configure' script at the top-level dir.
>
> So, the message is likely to totally confuse some users, and force other 
> users to keep local
> modifications to boost. Can we either remove this check, or assume that 
> unknown version of
> compiler is identical in behaviour to the last known one?

Hello,

this seams reasonable for new versions of already known compilers. For not 
know compilers the question is what would be the default value. One 
possibility is to provide a user define that give the default known 
compiler, the other preserve the error.

#else // UNKNOWN_COMPILER
#    if defined(BOOST_UNKNOWN_COMPILER_DEFAULT)
#        if !defined(BOOST_DISABLE_UNKNOWN_COMPILER_WARNING)
#             warning "Unknown compiler - please run the configure tests and 
report the results"
#        endif
#        if BOOST_UNKNOWN_COMPILER_DEFAULT=compX_versionY
                // do as for compX_versionY
#        else
                // ...
#        endif
#    else
#             error "Unknown compiler - please run the configure tests and 
report the results"
#    endif
#endif

Anyway I think that the warning should be preserved (adding the address of 
the page explaining how to do that will help) and maybe this could be 
protected with conditional compilation.

#if !defined(BOOST_DISABLE_UNKNOWN_COMPILER_VERSION_WARNING)
#     warning "Unknown compiler version - please run the configure tests and 
report the results (http://www.boost.org/...."
#endif

Best

Vicente