Require C++14 when building compilerplugins

[Stephan Bergmann]

On 21/08/2019 13:10, Stephan Bergmann wrote:
> For those building LO's Clang compilerplugins:  LLVM/Clang trunk has 
> switched to C++14 for building, and that makes it harder to maintain a 
> compilerplugins codebase that can be built both against old versions of 
> LLVM/Clang, which only required -std=c++11 in COMPILER_PLUGINS_CXX, and 
> against LLVM/Clang trunk.
> 
> Hence, <https://gerrit.libreoffice.org/#/c/77878/> "Require C++14 when 
> building compilerplugins" proposes that we unconditionally make 
> -std=c++14 the minimum in COMPILER_PLUGINS_CXX for building 
> compilerplugins on master.
> 
> Any objections?

Yes, the tinderboxes had objections (see the Gerrit change for details), 
so I cancelled this.