[erlang-bugs] Suicide by module_info

[Tuncer Ayaz]

On Sun, Apr 26, 2015 at 10:46 PM, Richard Carlsson
<carlsson.richard@REDACTED> wrote:
> On Sun, Apr 26, 2015 at 10:40 PM, Tuncer Ayaz <tuncer.ayaz@REDACTED> wrote:
> >
> > Could it be that erlang:get_module_info/1 is undocumented and
> > therefore underused? I don't think I ever called get_module_info/1
> > and I suspect everyone just uses foo:module_info/0,1, which
> > interestingly works after a successful code:delete(foo) call.
> >
> > The crash is a bug, but this might explain how it went unnoticed.
> >
> > Do you think the following is the right behavior?
> >
> > > c(foo).
> > {ok,foo}
> > > code:delete(foo).
> > true
> > > foo:module_info().
> > [{module,foo},
> > ...]
> >
> > I mean, I would expect fully qualified calls to foo:module_infi/0 to
> > fail once code:delete(foo) succeeds. Or is this how it's supposed to
> > behave?
>
>
> That's how things are supposed to work. If the foo is deleted when
> you call foo:module_info(), it will simply get reloaded and then
> called, just as if foo had not been previously loaded at all.

Of course error_handler:undefined_function/3 takes care of that.
Stupid thinko on my part to be blamed on posting late at night, making
me look like someone who never tried to write a module named
error_handler just to notice the interesting effects :).