[metapost] Uninitialized variable sometimes causing malformed TFM files

Marcel Fabian Krüger tex at 2krueger.de
Sun Jun 16 15:40:34 CEST 2019


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?

Best regards,
Marcel





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