[cmake-developers] cmake_cxx_link_executable issue

[Nils Gladitz]

On 06/24/2014 09:15 AM, Piotr Bialek wrote:

This might have been more appropriate for the user's mailing list since 
it does not involve development of CMake itself.

> I'm trying to cross compile with clang. I set cmake_compiler,
> cmake_linker, etc.
> During the linking CXX executable all flags, libs, files, etc. are
> getting  from somehow created file ./Main/CMakeFiles/Build.dir/link.txt.
>
> The problem is, that when I change linker by setting
> CMAKE_CXX_LINK_EXECUTABLE, no files or flags are generated in link.txt
> and I get message like: "x86_64-pc-linux-gnu-ld: no input files".

The CMAKE_CXX_LINK_EXECUTABLE variable does not refer to the linker 
executable.
It contains the rule used to link executables:

http://www.cmake.org/cmake/help/v3.0/variable/CMAKE_LANG_LINK_EXECUTABLE.html

You shouldn't have to modify it.

For a link CMake calls the compiler (and the compiler invokes the linker).

To set the compiler you can use: 
http://www.cmake.org/cmake/help/v3.0/variable/CMAKE_LANG_COMPILER.html

Or the CC and CXX environment variables.

The compilers have to be set on the initial CMake run.

For a native build with clang on GNU/Linux this can be as simple as e.g.:
   CC=clang CXX=clang++ cmake [...]

Nils