gnu: imagemagick: Add 'imagemagick/stable' variant.

* gnu/packages/imagemagick.scm (imagemagick/stable): New variable.
(imagemagick): This is now an alias to 'imagemagick/stable'.

1 files changed, 16 insertions, 1 deletions

diff --git a/gnu/packages/imagemagick.scm b/gnu/packages/imagemagick.scm
index cc5f1de4bf..528fb9eb25 100644
--- a/gnu/packages/imagemagick.scm
+++ b/gnu/packages/imagemagick.scm
@@ -44,7 +44,19 @@
   #:use-module (gnu packages xml)
   #:use-module (gnu packages xorg))
 
-(define-public imagemagick
+;; This is a variant of the 'imagemagick' package that is not updated often.
+;; It is intended to be used as a native-input at build-time only, e.g. by
+;; 'gtk-doc' (via 'dblatex') for generating package documentation.  This
+;; allows the main 'imagemagick' package to be freely updated on the 'master'
+;; branch without triggering an excessive number of rebuilds.
+;;
+;; Normally the grafts mechanism would be used, but there are often
+;; difficulties grafting imagemagick, e.g. because upstream changes the ABI
+;; between micro version updates.  Also, the overwhelming majority of
+;; dependencies on imagemagick are via 'gtk-doc' in 'native-inputs', where
+;; grafting is ineffective.  See:
+;; <https://lists.gnu.org/archive/html/guix-devel/2021-03/msg00381.html>.
+(define-public imagemagick/stable
   (package
     (name "imagemagick")
     ;; The 7 release series has an incompatible API, while the 6 series is still
@@ -127,6 +139,9 @@ transform images, adjust image colors, apply various special effects, or draw
 text, lines, polygons, ellipses and Bézier curves.")
     (license (license:fsf-free "http://www.imagemagick.org/script/license.php"))))
 
+(define-public imagemagick
+  imagemagick/stable)
+
 (define-public perl-image-magick
   (package
     (name "perl-image-magick")