malloc: performance improvements and bugfixes

[Paul Eggert]

On 01/26/2016 01:57 PM, Florian Weimer wrote:
> One change you can make*today*  is to include <malloc.h> in src/emacs.c
> (conditionally for dlmalloc), and not just the autoconf test case.

Emacs has included <malloc.h> for decades, in src/alloca.c, so this part 
is already done.

> you will actually see new deprecation warnings as they appear in
> the header file.

In practice this kind of deprecation warnings tends to be more trouble 
than it's worth. We already know about the compatibility issues, and 
don't need the deprecation warnings to remind us. The warnings will 
probably cause needless work by users who will not understand the 
details and who will send us low-value bug reports.

Come to think of it, how can we shut the deprecation warnings off? There 
should be an easy way for Emacs to do that.