filerw.c: (in function f)
filerw.c:6:14: Invalid transfer from rw_write f2 to rw_read (Must reset file
                  between write and read.): fgetc(..., f2, ...)
   filerw.c:1:72: f2 becomes rw_write
   filerw.xh:3:38: f1 becomes rw_read
filerw.c:8:22: Invalid transfer from rw_read f1 to rw_write (Must reset file
                  between read and write.): fputc(..., f1, ...)
   filerw.c:1:39: f1 becomes rw_read
   filerw.xh:4:44: f1 becomes rw_write
filerw.c:12:14: Invalid transfer from rw_write f1 to rw_read (Must reset file
                   between write and read.): fgetc(..., f1, ...)
   filerw.c:10:22: f1 becomes rw_write
   filerw.xh:3:38: f1 becomes rw_read

Finished checking --- 3 code warnings, as expected

file.c: (in function f)
file.c:14:5: Control branches merge with incompatible states for fout (closed
                and open)
   file.c:3:27: fout becomes implicitly open
   file.c:13:14: fout becomes closed
file.c:23:5: Control branches merge with incompatible states for fin (closed
                and open)
   file.c:3:16: fin becomes implicitly open
   file.c:22:14: fin becomes closed
file.c:25:10: Variable res used before definition

Finished checking --- 3 code warnings, as expected

Finished checking --- no warnings