Original bug ID: 4659
Reporter: oliver
Assigned to: @alainfrisch
Status: closed (set by @xavierleroy on 2015-12-11T18:07:27Z)
Resolution: fixed
Priority: normal
Severity: minor
Version: 3.10.2
Target version: 4.01.0+dev
Category: ~DO NOT USE (was: OCaml general)
Related to: #4598 #5070
Monitored by: oliver @Chris00

Bug description

I get the following error message:

===============
oliver@siouxsie:/Desktop/Overwrite_file$ ocamlc unix.cma buggy.ml
File "buggy.ml", line 20, characters 4-321:
Warning F: this function application is partial,
maybe some arguments are missing.
oliver@siouxsie:/Desktop/Overwrite_file$

Line 20 has length of 41 bytes!

The bug of my program is located in line 29,
where I used Printf.printf, expecting an arg, but do not provide it.

This means: the partial application is correctly mentioned by the compiler,
but the line and char-in-line is reported wrongly.

The problem occurs with ocamlc, ocamlopt and ocaml.

Additional information

For first overview, I provide the result of "$ nl -ba buggy.ml",
but I will attach the file for your convenience:

 1	
 2	let mb x = x * 1024 * 1024
 3	
 4	open Unix
 5	
 6	let _ =
 7	  let filename = Sys.argv.(1) in
 8	  let filesize = (stat filename).st_size in
 9	  Printf.printf "%d\n" filesize;
10	
11	  let restbytes = ref filesize in
12	
13	  let strlen = mb 100 in
14	  let string = String.make strlen ' ' in
15	  let writesize = ref strlen in
16	
17	  let fd = openfile filename [O_RDWR] 0o640 in
18	  while !restbytes > 0
19	  do
20	    writesize := (min !restbytes strlen);
21	
22	Printf.printf "restbytes: %d, writesize: %d\n" !restbytes !writesize;
23	flush Pervasives.stdout;
24	
25	    let num = write fd string 0 !writesize in
26	    restbytes := max 0 (!restbytes - num );
27	
28	Printf.printf "(just written: %d)\n" num;
29	Printf.printf "restbytes: %d\n-----------\n" (* HERE IS THE BUG! *)
30	
31	  done;
32	  close fd
33	
34	
35

File attachments

• buggy.ml