[all-commits] [llvm/llvm-project] e3ae2a: [llvm][CMake] Check dependency cxx source compiles...

[Eric Kilmer via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: e3ae2a52d2232e3b41caa9cf1197c24130249ddd
      https://github.com/llvm/llvm-project/commit/e3ae2a52d2232e3b41caa9cf1197c24130249ddd
  Author: Eric Kilmer <eric.d.kilmer at gmail.com>
  Date:   2023-10-18 (Wed, 18 Oct 2023)

  Changed paths:
    M llvm/cmake/modules/FindFFI.cmake
    M llvm/cmake/modules/FindTerminfo.cmake

  Log Message:
  -----------
  [llvm][CMake] Check dependency cxx source compiles (#68549)

If a CMake project doesn't enable the C language, then the CMake FFI and
Terminfo find modules will fail their checks for compilation and
linking.

This commit allows projects to enable only C++ by first checking if a C
compiler is set before testing C source compilation; if not, it checks
whether C++ compilation succeeds.

Fixes #53950