Fix build error with GCC by forcing Clang compiler in CMake on android/aarch64 (ggml-org#242)

GCC does not recognize Clang-specific warning flags like
-Wunreachable-code-break and -Wunreachable-code-return, which are passed
by upstream submodules (e.g., ggml). This patch forces CMake to use Clang
via command-line arguments, avoiding the need to patch nested submodules.

This resolves compiler errors without modifying submodule source code.

Author: Benjamin-Wegener

setup_env.py

@@ -199,7 +199,7 @@ def compile():
         logging.error(f"Arch {arch} is not supported yet")
         exit(0)
     logging.info("Compiling the code using CMake.")
-    run_command(["cmake", "-B", "build", *COMPILER_EXTRA_ARGS[arch], *OS_EXTRA_ARGS.get(platform.system(), [])], log_step="generate_build_files")
+    run_command(["cmake", "-B", "build", *COMPILER_EXTRA_ARGS[arch], *OS_EXTRA_ARGS.get(platform.system(), []), "-DCMAKE_C_COMPILER=clang", "-DCMAKE_CXX_COMPILER=clang++"], log_step="generate_build_files")
     # run_command(["cmake", "--build", "build", "--target", "llama-cli", "--config", "Release"])
     run_command(["cmake", "--build", "build", "--config", "Release"], log_step="compile")
 
@@ -229,4 +229,4 @@ def signal_handler(sig, frame):
     args = parse_args()
     Path(args.log_dir).mkdir(parents=True, exist_ok=True)
     logging.basicConfig(level=logging.INFO)
-    main()
+    main()