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On Mon, Apr 19, 1999 at 04:18:54PM -0230, Greg Harvey wrote: >forcer <forcer@mindless.com> writes: >> f = scm_must_malloc(sizeof(some_struct)); >> f->data = scm_must_malloc(size); >> >> and there won't be enough free memory for the second >> scm_must_malloc even after gc, the allocated memory in f is >> lost and won't be free'd. Is that true? > >Nope. That's quite interesting, and i'd like to know how Guile does this. I looked at the sourcecode to scm_must_malloc, and i don't see how the data stored in f could be freed. Recalling what will happen in the scenario described above: - f = scm_must_malloc(sizeof(some_struct)); scm_must_malloc calls malloc and returns the pointer. It doesn't keep track of it in any way except to increase the scm_mallocated global variable (i just rechecked the source on this) - f->data = scm_must_malloc(size); scm_must_malloc calls malloc and notices that it couldn't get enough memory. So it calls gc, and after that malloc again. Still, not enough free memory, so it throws an exception, which also bypasses our function. So after this, the memory pointed to by f is not referenced anywhere. Even if it would, the GC would have no way to tell wether it's used anywhere, since it surely doesn't contain a SCM value. So you say that still it will be freed, and i wonder how. I'm sorry if my first question didn't describe the problem properly. -forcer -- ((email . "forcer@mindless.com") (www . "http://webserver.de/forcer/") (irc . "forcer@#StarWars (IRCnet)") (pgp . "key available on my website"))