bug#42844: 27.1; Emacs 27.1: SVG file not rendered as image

[phillip.lord@russet.org.uk]

On 2020-08-15 18:44, Eli Zaretskii wrote:
>> Cc: 42844@debbugs.gnu.org
>> From: "gbiotti@gmail.com" <gbiotti@gmail.com>
>> Date: Sat, 15 Aug 2020 19:29:30 +0200
>> 
>> > Phillip, could you please look into this?  The missing DLLs should be
>> > added to the bundle.
>> 
>> It turns out that this is not enough.
>> I copied the three dll from the 26.3 bundle and run the test again:
>> 
>> (image-type-available-p 'svg) => nil
>> 
>> And obviously the svg file is shown as text.
> 
> Then using the same dependency tool, please look for more missing
> DLLs.  There must be others.
> 
>> I can make it work only by operating a Frankestein mix between old 
>> 26.3
>> bundle (with deps) and 27.1 bundle (with deps).
> 
> I don't understand what that means, sorry.

It probably means unpacking the 26.3 deps bundle over Emacs 27.1, or 
some mixture of the two. As the 26.3 bundle had a lot more dependencies 
that's not a surprise. Specifically, the problem is probably the logic 
in Emacs-27.1 that skips glib2 as a dependency. IIRC, that brings in 
python and many other of the packages from msys2 which made Emacs-26.3 
so huge.

The librsvg dependency itself is correctly given when I build the zips 
package.

Phil