Subject: Re: bug#7722: 24.0.50; Finding this C++ header file drops emacs into a infinite loop

From: Chong Yidong <[email-masked]>
Date: Sat, 22 Jan 2011 15:37:24 -0500

Tassilo Horn <[email-masked]> writes:

> Orininally reported by Caligo <[email-masked]>
>
> He uses GNU Emacs 23.2.1 (x86_64-pc-linux-gnu, GTK+ Version 2.20.1),
> but the bug in still in the current bzr trunk.
>
> 1. emacs -Q bug.hpp
> 2. emacs loops infinitely using 100% CPU resources
>
> The offending file is that (according to the original reporter, the
> spaces and empty lines are needed):

I can reproduce this (file attached for convenience).  Alan, could you
take a look?  Looks like a loop in c-forward-<>-arglist-recur:

Lisp Backtrace:
"c-forward-<>-arglist-recur" (0xffff4528)
"c-forward-<>-arglist-recur" (0xffff4708)
"c-forward-<>-arglist-recur" (0xffff48e8)
"c-forward-<>-arglist-recur" (0xffff4ac8)
"c-forward-<>-arglist-recur" (0xffff4ca8)
"c-forward-<>-arglist-recur" (0xffff4e88)
"c-forward-<>-arglist-recur" (0xffff5068)
"c-forward-<>-arglist-recur" (0xffff5248)
"c-forward-<>-arglist-recur" (0xffff5428)
"c-forward-<>-arglist-recur" (0xffff5608)
"c-forward-<>-arglist-recur" (0xffff57e8)
"c-forward-<>-arglist-recur" (0xffff59c8)
"c-forward-<>-arglist-recur" (0xffff5ba8)
"c-forward-<>-arglist-recur" (0xffff5d88)
"byte-code" (0xffff5e60)
"c-forward-<>-arglist" (0xffff6208)
---Type <return> to continue, or q <return> to quit---
"c-forward-name" (0xffff63e8)
"c-forward-type" (0xffff65c8)
"c-forward-decl-or-cast-1" (0xffff67f8)
0xee3c20 PVEC_COMPILED
"c-find-decl-spots" (0xffff6bb8)
"c-font-lock-declarations" (0xffff6dd8)
"font-lock-fontify-keywords-region" (0xffff6fc8)
"font-lock-default-fontify-region" (0xffff7198)
"font-lock-fontify-region" (0xffff7440)
"run-hook-with-args" (0xffff7438)
"byte-code" (0xffff7520)
"jit-lock-fontify-now" (0xffff7938)
"jit-lock-function" (0xffff7cc8)

class ConversionConsole : public QWidget{

private:
  typedef boost::array<InputLine, 22> InputLines;

  typedef cons<XYZ, cons<xyY, cons<Lab, cons<LCHab, cons<Luv, cons<LCHuv,
          cons<AdobeRGB, cons<AppleRGB, cons<BestRGB, cons<BetaRGB,
  	  cons<BruceRGB, cons<CIERGB, cons<ColorMatchRGB, cons<DonRGB4,
  	  cons<ECIRGB, cons<EktaSpacePS5, cons<NTSCRGB, cons<PAL_SECAMRGB,
  	  cons<ProPhotoRGB, cons<SMPTE_CRGB, cons<sRGB, cons<WideGamutRGB
  	  > > > > > > > > > > > > > > > > > > > > > > ColorSpaces;

};