bug#36597: 27.0.50; rehash hash tables eagerly in pdumper

[Eli Zaretskii <eliz@gnu.org>]

> Cc: larsi@gnus.org, pipcet@gmail.com, 36597@debbugs.gnu.org
> From: Paul Eggert <eggert@cs.ucla.edu>
> Date: Wed, 12 Aug 2020 12:11:09 -0700
> 
> I looked into the MinGW situation and the problem seems to be that MinGW defined 
> a macro _INTPTR_T_DEFINED that it no longer defines, and Gnulib was keying off 
> that no-longer-present macro.

I think _INTPTR_T_DEFINED is still being used, but only by MinGW64.  I
use mingw.org's MinGW, where that macro was never used.

However, both MinGW flavors typedef intptr_t as 'int', not 'long int',
on 32-bit platforms.

> I installed a patch for that in Gnulib here:
> 
> https://lists.gnu.org/r/bug-gnulib/2020-08/msg00088.html
> 
> and migrated the patch into Emacs. Hope it fixes things.

It does here, thanks.  I hope someone will be able to make sure
MinGW64 builds are not adversely affected (I don't think they should
be).

> As an aside, we're spending too much time on pdumper.c code that has no effect 
> because dump_trace never outputs anything. How about if I remove dump_trace and 
> its callers? Although dump_trace may have been useful when the portable dumper 
> got developed, it's just a developer time sink now.

I have no opinion on this, but I'd like to hear from Daniel (CC'ed)
what he thinks.