In case CC is set try to split it by spaces into a command and
arguments. This is the same behaviour as in dmd.
Signed-off-by: Andrei Horodniceanu <a.horodniceanu@proton.me>
I thought DMD would create the temp .i file in the same directory
as the .c file, but it creates it in the current working dir.
Create them in a dedicated new temp directory now, to prevent
collisions (parallel compiler invocations in the same working dir
etc. etc.).
