bug#30670: 26.0.91; PNG files on Windows

[Eli Zaretskii]

> From: Alex Schröder <kensanata@gmail.com>
> Date: Thu, 1 Mar 2018 20:25:23 +0000
> Cc: 30670@debbugs.gnu.org
> 
> On Thu, Mar 1, 2018 at 7:29 PM, Eli Zaretskii <eliz@gnu.org> wrote:
> 
>  > From: kensanata@gmail.com
>  > c:/Portable Programs/emacs-26.0.91-x86_64/bin $ ls lib* | grep "png"
>  > libpng-config
>  > libpng16-16.dll
>  > libpng16-config
> 
>  Where did you get those PNG DLLs?
> 
> These three files are in emacs-26.0.91-x86_64.zip which I got from
> https://alpha.gnu.org/gnu/emacs/pretest/windows/

How do you invoke Emacs from that installation?

Are there any other versions of libpng16-16.dll on that system?

Does pngfix.exe work (it should be in the same directory as
libpng16-16.dll)?

And finally, what is the value of libpng-version in your Emacs?