Revert some ocaml code to ocaml 4.01 compatibility

src/Makefile

-OCAMLBUILD=/home/ploc/.opam/4.03.0+trunk/bin/ocamlbuild -classic-display -use-ocamlfind -no-links 
+OCAMLBUILD=/usr/bin/ocamlbuild -classic-display -use-ocamlfind -no-links 
 
 prefix=/home/ploc/Local
 exec_prefix=${prefix}

src/backends/C/c_backend_common.ml

@@ -24,7 +24,7 @@ let print_version fmt =
     (if !Options.mpfr then "MPFR multi-precision" else "(double) floating-point")
 
 let file_to_module_name basename =
-  let baseNAME = String.uppercase_ascii basename in
+  let baseNAME = String.uppercase basename in
   let baseNAME = Str.global_replace (Str.regexp "\\.\\|\\ ") "_" baseNAME in
   baseNAME
 

src/backends/Horn/horn_backend.ml

@@ -52,7 +52,7 @@ end
 let load_file f =
   let ic = open_in f in
   let n = in_channel_length ic in
-  let s = Bytes.create n in
+  let s = String.create n in
   really_input ic s 0 n;
   close_in ic;
   (s)