Re: [boost] [build] Problems with VC14 and MSPDB140.DLL (was: [testing][teeks] MSVC-14 errors about MSPDB140.DLL)

Subject: Re: [boost] [build] Problems with VC14 and MSPDB140.DLL (was: [testing][teeks] MSVC-14 errors about MSPDB140.DLL)
From: Gavin Lambert (gavinl_at_[hidden])
Date: 2015-08-10 20:35:51

Mere moments ago, quoth I:
> Ok, examining msvc.jam I think I've found the issue.  It defaults to
> "x86_amd64" (cross compiler), and then swaps this to "amd64" (native
> compiler) if the environment variable PROCESSOR_ARCHITECTURE is set to
> AMD64.
>
> However this will only be the case if the process executing the jam file
> is also 64-bit.  A 32-bit process running under WOW64 will see "x86" for
> that environment variable, just like it would on 32-bit Windows.
>
> So, either Boost.Build itself needs to be a 64-bit process, or it needs
> to be more clever at detecting a 64-bit architecture even as a 32-bit
> process.  The simplest way of doing the latter is to read
> PROCESSOR_ARCHITEW6432, which will be unset for native 32 or 64-bit and
> set to AMD64 on 32-bit WOW64.  (ie. the jamfile should assume native
> 64-bit if either of PROCESSOR_ARCHITECTURE or PROCESSOR_ARCHITEW6432 are
> set to AMD64.)

PR for the latter workaround: https://github.com/boostorg/build/pull/87