Memory leak with octave cygwin DLD calls

[John W. Eaton]

On 23-Apr-2005, Andy Adler <address@hidden> wrote:

| I've been trying to debug a memory leak problem with
| cyginw octave. It's been there since at least 2.1.60 and
| is still in 2.9.2. I've now simplified it to this:
| 
| Using a simple DLD function like
|     $ cat zno.cpp
|     #include <octave/oct.h>
| 
|     DEFUN_DLD (zno, args, , " "  ) {
|         octave_value retval= 0.0;
|         return retval;
|     }
| 
| call octave like this
| 
|     echo 'for i=1:1e8; x=zno ;end'  | octave -qfH
| 
| and watch the process monitor size for octave climb.
| I calculate about 16 bytes leak per function call.
| 
| This also happens with builtin functions
| 
|     echo 'for i=1:1e8; x=sort(1) ;end'  | octave -qfH
| 
| If octave is compiled statically, there is no memory
| leak.
| 
| I'm not sure where to look to debug this.

I don't see the leak on a Debian system, so I'd guess that it is
something in a system library or (perhaps less likely) the code
generated by GCC on the Cygwin system.  I'm not sure precisely how to
debug it either.  Can you run something like valgrind to give some
clues?

jwe