GH Actions: Use pre-installed clang packages

Also fix the run by setting up the environment in non-deprecated way.

Always run with --debug to understand better what sort of stuff is happening in
the background. Also split out the bmake bootstrap stage (takes about 31s on
ubuntu, but 1m14 on macOS?)

Drops the dependency on coreutils (realpath, nproc) and thus (?) fixes macOS to
be just as fast (4 logical cores vs 2 physical cores before, go figure.)

Reviewed by:		arichardson

1 files changed, 6 insertions, 2 deletions

diff --git a/tools/build/make.py b/tools/build/make.py
index 7cfe8a0ee08f7..fefd2d2dd61bf 100755
--- a/tools/build/make.py
+++ b/tools/build/make.py
@@ -115,6 +115,9 @@ def check_required_make_env_var(varname, binary_name, bindir):
                  " does not exist")
     new_env_vars[varname] = guess
     debug("Inferred", varname, "as", guess)
+    global parsed_args
+    if parsed_args.debug:
+        run([guess, "--version"])
 
 
 def default_cross_toolchain():
@@ -188,6 +191,9 @@ if __name__ == "__main__":
 
         if parsed_args.host_compiler_type == "gcc":
             default_cc, default_cxx, default_cpp = ("gcc", "g++", "cpp")
+        # FIXME: this should take values like `clang-9` and then look for
+        # clang-cpp-9, etc. Would alleviate the need to set the bindir on
+        # ubuntu/debian at least.
         elif parsed_args.host_compiler_type == "clang":
             default_cc, default_cxx, default_cpp = (
                 "clang", "clang++", "clang-cpp")
@@ -235,7 +241,5 @@ if __name__ == "__main__":
         shlex.quote(s) for s in [str(bmake_binary)] + bmake_args)
     debug("Running `env ", env_cmd_str, " ", make_cmd_str, "`", sep="")
     os.environ.update(new_env_vars)
-    if parsed_args.debug:
-        input("Press enter to continue...")
     os.chdir(str(source_root))
     os.execv(str(bmake_binary), [str(bmake_binary)] + bmake_args)