bug#14553: 24.3.50; C-g doesn't break inf-loop

[Katsumi Yamaoka]

Hi,

Start Emacs with the -Q option.
Eval the form: (while t)

Then I get unable to break it.  So is Emacs 24.3.  This may happen
only on Cygwin, though.  It makes me hard to debug a code suspected
to have an infinite loop.

In GNU Emacs 24.3.50.1 (i686-pc-cygwin, X toolkit, Xaw3d scroll bars)
 of 2013-06-04 on localhost
Bzr revision: 112842 michael.albinus@gmx.de-20130603193806-1f2pilg1t709mqyg
Windowing system distributor `The Cygwin/X Project', version 11.0.11401000
Configured using:
 `configure --verbose --with-x-toolkit=lucid --without-imagemagick
 --without-dbus --without-gconf --without-gsettings'