External LLVM toolchain not consistently locating c++ when compiling ports

[Stefan Esser]

Am 29.10.17 um 08:48 schrieb Mark Millard:
> So without system clang (or system gcc 4.2.1) and only
> with llvm40 I expect that there is no c++ command at all.
> The issue would not be an overly-specific path: no path
> would work.
> 
> Rust needs to not be looking for a c++ command at all.
> It needs to be using ${CXX} and the like that would
> need to involve clang++50 .
> 
> But you can make a local workaround by creating your
> own c++ command someplace in the paths being checked,
> either linking to or copying clang++40 to produce the
> c++ . c++ might not be the only file needing such
> a technique.

This situation should be covered by the new BINARY_ALIAS feature,
which makes a symbolic link to some binary available under a new
name and adds the location of that link to the PATH:

https://svnweb.freebsd.org/ports?view=revision&revision=451772

In this particular case:

BINARY_ALIAS	c++=clang++50

Regards, STefan