Re: @displaymath \leqalignno problem for pdf output

[Gavin Smith]

On Thu, Nov 12, 2020 at 08:15:59PM +0100, Christopher Dimech wrote:
> 
> I have been testing some more and we are getting some serious problems.
> Have tried the following two constructs
> 
> ------------------------------------
> 
> 1. First Test - This works in html, but fails in pdf ($$ $$ are required)
> 
> @displaymath
> \leqalignno{
>    \int v(t)\, dt &= u(t) + C&[3.1]\cr
>    \int v(t)\, dt &= u(t) + H&[3.2]\cr
> }
> @end displaymath
> 
> ---------------------------------------

This appears to be a bug in the implementation in texinfo.tex but it
will take me some time to work out what is going on.

There is actually a help message:

! Missing $$ inserted.
<to be read again> 
                   @begingroup 
@parseargusing ...>@def @argtorun {#2}@begingroup 
                                                  @obeylines @spaceisspace #...
l.15 @end
          displaymath
? h
Displays can use special alignments (like \eqalignno)
only if nothing but the alignment itself is between $$'s.

?