On Sat, Jan 21, 2017 at 8:04 PM, Fabrice Popineau <fabrice.popineau@gmail.com> wrote:

> My point is : ImageMagick is made available by dynamically loading 2 dlls.
> If they are not installed, then the feature is disabled (as far as I remember).

If Emacs on Windows is built to use the DLLs, and they are not available (let's say you downloaded a binary tarball built with Imagemagick support, but you don't have the DLLs in your system), Windows won't allow emacs.exe to run. That's a big problem.

> What happens if the jpeg or xpm or png dlls are not found ? 

Nothing, because they are not statically linked. If Emacs was built with jpeg support (or png, etc.), it will check at runtime (and on demand, the first time a jpeg function is needed) that the jpeg DLL can be loaded. If not, the function will fail and Emacs will take note that the DLL is unavailable.