GIF loading failure

[lehitoskin]

I have a GIF file I'm trying to load into a bitmap and I get this failure:

> (define img (build-path "003.gif"))
> (define bmp
    (let ([in (open-input-file img)])
      (define bitmap (make-object bitmap% in 'gif/alpha))
      (close-input-port in)
      bitmap))
; vector-set!: index is out of range
;   index: 4096
;   valid range: [0, 4095]
;   vector: '#(-1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1
;     -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1...
; [,bt for context]
> ,bt
; vector-set!: index is out of range
;   index: 4096
;   valid range: [0, 4095]
;   vector: '#(-1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1...
;   context...:
;    /usr/share/racket/pkgs/draw-lib/racket/draw/private/lzw.rkt:124:6: loop
;    /usr/share/racket/pkgs/draw-lib/racket/draw/gif.rkt:113:0: read-image
;    /usr/share/racket/pkgs/draw-lib/racket/draw/gif.rkt:141:6: loop
;    /usr/share/racket/pkgs/draw-lib/racket/draw/gif.rkt:128:0: read-gif
;    /usr/share/racket/pkgs/draw-lib/racket/draw/gif.rkt:182:0: gif->rgba-rows
;    /usr/share/racket/pkgs/draw-lib/racket/draw/private/bitmap.rkt:381:4: do-load-bitmap method in bitmap%
;    /usr/share/racket/pkgs/draw-lib/racket/draw/private/syntax.rkt:234:25
;    /usr/share/racket/pkgs/draw-lib/racket/draw/private/bitmap.rkt:156:2
;    /usr/share/racket/collects/racket/private/class-internal.rkt:3553:0: continue-make-object
;    /usr/share/racket/collects/racket/private/class-internal.rkt:3553:0: continue-make-object
;    /usr/share/racket/collects/racket/private/class-internal.rkt:3507:0: do-make-object
;    /usr/share/racket/pkgs/xrepl-lib/xrepl/xrepl.rkt:1443:0
; /usr/share/racket/collects/racket/private/misc.rkt:88:7

It appears to be a problem with gif->rgba-rows, but I'm not familiar enough with the internals to say for sure. For reference, here's the GIF I'm using.

[lehitoskin]

For reference, this is still an issue in Racket v6.12 and it happens on just about half of the gifs I have in my library.

[jbclements]

This is... an animated GIF? Does Racket support animated GIFs?

[lehitoskin]

@jbclements while the animation isn't handled, it'll still load a static image.