Re: Removal of unexec support from glibc malloc

[Stefan Monnier]

> AFAICS, it happens due to the following:
>   . We call regex.c functions, which reuse an allocated buffer,
>     extending it (via realloc) as needed; that buffer gets frozen with
>     malloc arena used during dumping
>   . We delete the terminal frame used by temacs and free its resources
>   . Not 100% sure, but I think we also release/reallocate some
>     font-related stuff
> It's easy to catch all those cases by setting a breakpoint on realloc
> and free during startup.

I guess that's what happens in practice, but I'd be surprised if there
aren't more cases that can happen in theory.  I'm thinking of memory
areas allocated for Elisp data which will *usually* stay live during the
lifetime of Emacs, but which could become free if we do things like
re-define some core datastructure (e.g. I'm thinking of things like
(setq global-map (copy-keymap global-map)).


        Stefan