[CMake] Relinking with Ninja broken in 3.7.0

[Bill Hoffman]

On 11/16/2016 11:36 AM, Mika Fischer wrote:
>
> I get the following error even though I'm on Linux and thus an ELF-based
> platform. This breaks all our builds...
>
> `The install of the <target> target requires changing an RPATH from
> the build tree, but this is not supported with the Ninja generator unless
> on an ELF-based platform.  The CMAKE_BUILD_WITH_INSTALL_RPATH variable may
> be set to avoid this relinking step.`
>
> Looking at cmGeneratorTarget.cxx#L1214, I see that there's no switch for
> ELF-based platforms, it just unconditionally throws a fatal error when
> relinking is required and ninja is being used...
>
> Is the error message misleading and this should actually work on Linux?
> Or is this not supposed to be working, and we should no longer use
> ninja? If so, why?
>
> CMAKE_BUILD_WITH_INSTALL_RPATH is not a viable alternative for us...
>
Did you start with a completely clean build tree?  Or did you maybe just 
remove the CMakeCache.txt file?

-Bill