[metapost] Uninitialized variable sometimes causing malformed TFM files

[Marcel Fabian Krüger]

On Sun, Jun 16, 2019 at 04:14:00PM +0200, luigi scarso wrote:
> On Sun, Jun 16, 2019 at 3:41 PM Marcel Fabian Krüger <tex at 2krueger.de>
> wrote:
> 
> > On Wed, Mar 20, 2019 at 08:26:22PM +0100, Marcel Krüger wrote:
> > >  ---- On Wed, 20 Mar 2019 19:01:08 +0100 luigi scarso <
> > luigi.scarso at gmail.com> wrote ----
> > >  >
> > >  >
> > >  > On Wed, Mar 20, 2019 at 6:54 PM Marcel Krüger <tex at 2krueger.de>
> > wrote:
> > >  > Thanks. There is one other thing, I do not really know if I would
> > describe it as a backward compatibility bug or a feature request:
> > >  >
> > >  > For non-"scaled" numbersystems, code like
> > >  >
> > >  > filldraw stroke z1e--z2e;
> > >  > (example taken from cmbase.mf, `left_bracket`)
> > >  >
> > >  > fail, because z1e-- is interpreted as z 1e- - instead of z1e --. So
> > z1e--z2e is equal to z1-z2e, leading to lots of errors.
> > >  >
> > >  > I understand that the new numbersystems and the exponential syntax
> > can lead to problems of this kind, but I think this could be avoided:
> > >  > Maybe a `e+` / `e-` could only be interpreted as exponential notation
> > if it is followed by a  digit? I do not think
> > >  > anyone would write "1e-" or "3e+" for 1 or 3, so it should not lead
> > to any breakage.
> > >  > On the other hand it would catch almost all cases where this is
> > invoked accidentially.
> > >  >
> > >  > A possible implementation of this change  is attached.
> > >  >
> > >  >
> > >  > hm it looks like a serious bug, and I fear I will not able to fix it
> > for next TL --- but I hope to put it into trunk immediately after the TL
> > code is frozen.
> > >  >
> > >
> > > Right, I am sorry for bringing this up so late in the TL cycle.
> > >
> > > One additional note on this: The behaviour described above (`1e-` being
> > interpreted as `1`) seems to be specific to the `double` mode.
> > > The `decimal` mode just fails because it is not able to parse the
> > number, which further reduces the risk of breaking some code by changing
> > the current
> > > behaviour.
> > >
> > > Also I attached a fixed version of the earlier patch, there was a
> > smaller error.
> > >
> > > Best regards,
> > > Marcel Krüger
> > >
> > >  >
> > >  > --
> > >  > luigi
> > >  >
> >
> > Hi,
> >
> > are there still plans to fix this?
> >
> >
> yes

Great, thank you.

Marcel