Richard Jones and I have been preparing to update to OCaml 5.0 in Rawhide.  Test builds are available in a COPR: https://copr.fedorainfracloud.org/coprs/jjames/OCaml5/.  We now have almost all OCaml-using packages built in the COPR, with the exception of half a dozen packages we intend to retire.

Haxe is the sole remaining package, but it is not compatible with OCaml 5.0.  I have a patch that fixes many of the incompatibilities, which I will attach to this bug.  However, even with that patch, building fails:

/usr/bin/ld: libs/objsize/libobjsize_stubs.a(c_objsize.o): in function
`c_rec_objsize':
/builddir/build/BUILD/haxe-4.3.1/_build/default/libs/objsize/c_objsize.c:359:
undefined reference to `caml_page_table_lookup'
/usr/bin/ld: libs/objsize/libobjsize_stubs.a(c_objsize.o): in function
`restore_colors':
/builddir/build/BUILD/haxe-4.3.1/_build/default/libs/objsize/c_objsize.c:387:
undefined reference to `caml_page_table_lookup'
/usr/bin/ld: libs/objsize/libobjsize_stubs.a(c_objsize.o): in function
`c_objsize':
/builddir/build/BUILD/haxe-4.3.1/_build/default/libs/objsize/c_objsize.c:450:
undefined reference to `caml_page_table_lookup'
/usr/bin/ld: /builddir/build/BUILD/haxe-4.3.1/_build/default/libs/objsize/c_objsize.c:413:
undefined reference to `caml_page_table_lookup'
/usr/bin/ld: /builddir/build/BUILD/haxe-4.3.1/_build/default/libs/objsize/c_objsize.c:426:
undefined reference to `caml_page_table_lookup'
/usr/bin/ld: libs/objsize/libobjsize_stubs.a(c_objsize.o):/builddir/build/BUILD/haxe-4.3.1/_build/default/libs/objsize/c_objsize.c:441:
more undefined references to `caml_page_table_lookup' follow

See https://github.com/ocaml-multicore/ocaml-multicore/issues/637; caml_page_table_lookup is not and will not be available in OCaml 5.x.

Reproducible: Always