You are correct; the problem only happens with a file:/// url. The
following executes without problem and emacs memory stays constant:
(dotimes (i 100) (w32-shell-execute "open" "c:/users/mario/desktop/x.html"))
With a file:/// url it triggers the bug:
(dotimes (i 100) (w32-shell-execute "open"
"file:///c:/users/mario/desktop/x.html"))

2015-04-04 15:19 GMT-06:00 Eli Zaretskii <eliz@gnu.org>:

> > Date: Sat, 4 Apr 2015 14:24:07 -0600
> > From: Mario Valencia <mariovalspi@gmail.com>
> > Cc: Daniel Colascione <dancol@dancol.org>, Stefan Monnier <
> monnier@iro.umontreal.ca>, 20220@debbugs.gnu.org
> >
> > I think the thread created is this:
> > SHCORE.DLL!Ordinal254+0x9a0 <- start address
>
> SHCORE.dll sounds like a Windows 8 version of shlwapi.dll, or maybe a
> part of it.  So this looks very similar to what I saw on that single
> Windows 7 system.
>
> Do you also see that the problem happens only if w32-shell-execute is
> called with a file:/// URL, and does not happen if it is called with a
> normal Windows file name?
>