UNIX style slashes in cflags file

Author: tannewt

ports/zephyr-cp/cptools/cpbuild.py

@@ -324,9 +324,13 @@ def __init__(self, srcdir: pathlib.Path, builddir: pathlib.Path, cmake_args):
         self.c_compiler = cmake_args["CC"]
         self.ar = cmake_args["AR"]
         self.cflags = cmake_args.get("CFLAGS", "")
+        print(self.cflags)
 
         self._cflags_tempfile = tempfile.NamedTemporaryFile()
-        self._cflags_tempfile.write(self.cflags.encode())
+
+        # Windows paths have \ as separator but ar wants them as / (like UNIX)
+        unix_cflags = self.cflags.replace("\\", "/")
+        self._cflags_tempfile.write(unix_cflags.encode())
         self._cflags_tempfile.flush()
         self.cflags_file = "@" + self._cflags_tempfile.name