minutes of ESC call ...

[Stephan Bergmann]

On 02/18/2016 05:38 PM, Michael Meeks wrote:
> * MSVC 14.0 / Drop MSVC 12.0 on master (DavidO)
>       + Improvement of C++14/C++17 standard
>       + bit rotted on master: dozen compilation errors
>       + Add Tinderbox to verify that it still works
>       + After release of 5.1 consider to discontinue support for MSVC 12.0 on master
>           * Looks like it's impossible to manage the switch period
>           * both compilers could be installed (?) on the same machine, to still use old compiler on 5.1
>       + Duplicated Python 3.3/3.5 trees, because upstream dropped support for MSVC 12.0
>       + plan was to use Windows Server 2016 + update baseline (Cloph)
>           + can setup the tech. preview 4 of Win. Server 2016 & have a t-box.
>           + but not convinced on deprecation yet.
>       + does 5.0 build with VS 2015 ? (Norbert)
>
>             + No. Requires Python 3.5
>
>               Only build on master
>
>           + if so, with the 2x new Windows box showing up
>              + install VS 2015 there.
>           + then take two others off-line & upgrade them too.
>       + even on master - with just VS 2015 - still have issues (Miklos)
>           + would be good for now to have a tinderbox to stop it breaking.
>       + not fond of multiple versions of compiler (Norbert)
>           + can hide problems.
>               + concerned we test with only the new compiler (Miklos)
>       + new Win boxes physically arrived
>           + being moved around at Manitu right now with Alex.
>           => put Win Server 2016 Preview 4 + VS 2015
>               - and bring them on-line and see how it goes.
>               + if problems building with 5.0 and 5.1 - re-think.
>       + is it confirmed 5.0 builds with VS 2015 ? (Norbert)
>           + No. Requires Python 3.5
>             Only build on master
>           + only 1x release left of 5.0.x - anyway (Cloph)
>               + to mid April/May.
>       => defer update until then.
>       + can we somehow restore Thorsten's t-box vs. 2015 ? (Michael)
>           + Thorsten's TB was shut down because of devenv.exe invocation
>             (mst__ has an idea how to fix it?)
>                + no idea (mst).
>       + migrating slaves of jenkins infra - is a bigger deal - needs a single
>         toolchain that builds all relevant versions (Norbert).
> AI:  => will setup a tinderbox VM for VS. 2015 (Cloph)
>       + would be good to back-port fixes to 5.1 too to be prepared for May.

What I noticed with my clang-cl build on Windows is that some of the 
external modules (at least external/libxmlsec/ExternalProject_xmlsec.mk) 
do not get built with whatever is configured as CC/CXX for LO, but 
determine that themselves, potentially picking an unexpected MSVC 
version if multiple ones are installed?

(It is rather harmless for my clang-cl case, where the main reason to 
build with clang-cl is more warnings, which we ignore in external 
modules anyway. So it doesn't really matter there that some external 
modules are built with MSVC instead of clang-cl.  But it might become a 
problem for MSVC 2013 vs. 2015 builds, when such an external DLL records 
a requirement on the "wrong" compiler runtime DLL.)