Re: [Module::Build] missing CBuilder

[Randy W. S. <ml...@th...>]

Marvin Humphrey wrote:
> Greets,
> 
> It looks like in some cases my XS distro KinoSearch may not be able to 
> installed via CPAN without extra intervention since the release of 
> Module::Build 0.28.  The problem seems to arise when Module::Build has 
> not been installed, and the passthrough Makefile.PL gets called.  After 
> you reply yes at the prompt asking if you want to install Module::Build, 
> it installs without ExtUtils::CBuilder, even on systems where 
> ExtUtils::CBuilder can be installed later via the CPAN shell without a 
> problem.
> 
> Is the answer to add ExtUtils::CBuilder to the build_requires hash?

Hmm, Module::Build itself doesn't require EU::CBuilder, so it is only a 
recommended prereq. BUT, modules that use M::B may have an indirect & 
implicit dependency on EU::CBuilder. I.E. They depend on an optional 
feature of M::B. This dependency is never explicitly mentioned anywhere 
so installs can fail.

Currently the only solution is to make the dependency explicit in your 
module's build files by listing EU::CBuilder in 'build_requires' as you 
already observed.

I wonder if there should be a better way to express this dependency. 
Maybe it could be declared like this:

use Module::Build features => qw( C_support );

Instead of having indirect prereqs listed in build files where it really 
has nothing directly to do with the distro. Module::Build could then do 
whatever magic is needed under the hood to add the appropriate prereqs.

Randy.