[bug#49625] [PATCH 1/2] gnu: Add gecode.

[Leo Prikler <leo.prikler@student.tugraz.at>]

* gnu/packages/maths.scm (gecode): New variable.
---
 gnu/packages/maths.scm | 71 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 71 insertions(+)

diff --git a/gnu/packages/maths.scm b/gnu/packages/maths.scm
index eeb32d554a..c052d33214 100644
--- a/gnu/packages/maths.scm
+++ b/gnu/packages/maths.scm
@@ -2008,6 +2008,77 @@ linear and quadratic objectives.  There are limited facilities for nonlinear
 and quadratic objectives using the Simplex algorithm.")
     (license license:epl1.0)))
 
+(define-public gecode
+  (package
+    (name "gecode")
+    (version "6.2.0")
+    (source (origin
+              (method git-fetch)
+              (uri (git-reference
+                    (url "https://github.com/Gecode/gecode")
+                    (commit (string-append "release-" version))))
+              (file-name (git-file-name name version))
+              (sha256
+               (base32
+                "0b1cq0c810j1xr2x9y9996p894571sdxng5h74py17c6nr8c6dmk"))
+              (modules '((guix build utils)))
+              (snippet
+               '(begin
+                  ;; delete generated sources
+                  (for-each delete-file
+                            '("gecode/kernel/var-imp.hpp"
+                              "gecode/kernel/var-type.hpp"))))))
+    (outputs '("out" "examples"))
+    (build-system gnu-build-system)
+    (arguments
+     `(#:configure-flags
+       (list (string-append "GLDFLAGS=-Wl,-rpath="
+                            (assoc-ref %outputs "out")
+                            "/lib")
+             "--enable-examples=no")
+       #:modules ((guix build gnu-build-system)
+                  (guix build utils)
+                  (ice-9 rdelim)
+                  (ice-9 popen))
+       #:phases
+       (modify-phases %standard-phases
+         (add-after 'build 'build-examples
+           (lambda* (#:key outputs #:allow-other-keys)
+             (invoke "make" "compileexamples")))
+         ;; The Makefile disrespects GLDFLAGS for some reason, so we have to
+         ;; patch it ourselves... *sigh*
+         (add-after 'install 'fix-rpath
+           (lambda* (#:key outputs #:allow-other-keys)
+             (let ((libdir (string-append (assoc-ref outputs "out") "/lib")))
+               (for-each
+                (lambda (file)
+                  (let* ((pipe (open-pipe* OPEN_READ "patchelf"
+                                          "--print-rpath" file))
+                         (line (read-line pipe)))
+                    (and (zero? (close-pipe pipe))
+                         (invoke "patchelf" "--set-rpath"
+                                 (string-append libdir ":" line)
+                                 file))))
+                (find-files libdir ".*\\.so$")))))
+         (add-after 'install 'install-examples
+           (lambda* (#:key outputs #:allow-other-keys)
+             (invoke "make" "installexamples"
+                     (string-append "bindir=" (assoc-ref outputs "examples")
+                                    "/bin"))))
+         ;; Tests depend on installed libraries.
+         (delete 'check)
+         (add-after 'fix-rpath 'check
+           (assoc-ref %standard-phases 'check)))))
+    (native-inputs
+     `(("patchelf" ,patchelf)
+       ("perl" ,perl)
+       ("sed" ,sed)))
+    (home-page "https://www.gecode.org")
+    (synopsis "Toolkit for developing constraint-based systems")
+    (description "Gecode is a C++ toolkit for developing constraint-based
+systems and applications.  It provides a modular and extensible solver.")
+    (license license:expat)))
+
 (define-public libflame
   (package
     (name "libflame")
-- 
2.32.0