Re: [groff] 1.18 mm: infinite loop with large vs

[Bill Brelsford]

The following bug still exists in 1.19.2.  I've identified the
problem -- see below.

On Wed May 21 2003 at 06:04 PM -0700, W M Brelsford wrote:
>                          Groff Bug Report
> 
> GROFF VERSION: 1.18
>  mm version: .\" $Id: m.tmac,v 2.14 2002/06/07 08:41:34 jhaegg Exp $
> 
> MACHINE: IBM-compatible PC
> 
> OS: Linux 2.4.18-14 (RedHat 8.0)
> 
> COMPILER: none (used groff-1.18-6 rpm)
> 
> INPUT FILES: foo.tr -- 4 lines:
> 
>       .S 27 29
>       .SP
>       foo
>       .SK
> 
> COMMAND LINE: groff -mm <foo.tr >foo.ps               (groff version of mm)
> 
> DESCRIPTION OF INCORRECT BEHAVIOUR:
> 
>    foo.tr:4: fatal error: input stack limit exceeded (probable infinite loop)
> 
>  and foo.ps contains the following for pages 1-199:
> 
>       %%Page: 1 1
>       %%BeginPageSetup
>       BP
>       %%EndPageSetup
>       /F0 27/address@hidden SF 6.75(-1)249.345 116 S(99 -)-6.75 E 0 Cg EP
> 
>  Happens whenever vertical spacing is "too big".  With ".S 27 60"
>  ".SP" can be omitted -- only the "foo" line is needed to cause
>  looping.
> 
>  Worked OK in 1.17.2 (RedHat 7.3).
> 
>  (If this is fixed in a newer version (1.18.1 or 1.19), how do I get
>  it?  The groff-*.tar.gz files don't seem to include tmac/m.tmac.)
> 
> SUGGESTED FIX [optional]:

In earlier versions, register pg*footer-size was set to 5 and
referenced as \\n[pg*footer-size]v.  In 1.18 it is set to 5v and
referenced as \\n[pg*footer-size]u.  This doesn't work because the
vertical spacing (v) can change by the time the register is
referenced.  Register pg*header-size has the same problem.

-- 
Bill Brelsford
address@hidden