[polyml] standard input contains a leading blank line? (5.5.2 with --enable-shared)

If the following is foo.ML:

fun doit () = let fun recurse i = case TextIO.inputLine TextIO.stdIn of NONE => () | SOME l => (print (Int.toString i ^ ": " ^ l); recurse (i + 1)) in recurse 1 end;

PolyML.export("mytest", doit);

and I then do

$ poly < foo.ML $ cc -o mytest mytest.o -lpolymain -lpolyml $ echo "hello, world" | ./mytest

I get

1: 2: hello, world

as output.

This is with a polyml 5.5.2 just downloaded from Sourceforge and configured with --enable-shared. I'm pretty sure this used to work (a minor feature of the HOL4 build process depended on it).

Michael