* Don't include stdio.h in caml/misc.h
There is no need to include stdio.h in caml/misc.h
This seems to have happened by accident in commit cddec18fde
On OpenBSD, stderr and stdout are macros defined in stdio.h
ppx_expect uses stderr and stdout as identifiers in
collector/expect_test_collector_stubs.c where caml/misc.h is included.
This confuses the C compiler, because the macro will get expanded where an identifier is expected.
* Remove fallback NULL definition in caml/misc.h
ISO C guarantees that NULL is defined in <stddef.h>
* include missing stdio in tests/compatibility/stub.c
madroach
Nicolás Ojeda Bär
David Allsopp