[bug#65155] [PATCH] gnu: mesa: Add native-search-paths.

[dan <i@dan.games>]

* gnu/packages/gl.scm (mesa) [native-search-paths]: Export XDG_DATA_DIRS.

According to
https://vulkan.lunarg.com/doc/view/1.3.231.1/linux/loader_and_layer_interface.html,
Vulkan loader search for manifest files in several directories.  Some of them
are in the $HOME directory, some of them are set during compile-time.  We
don't raelly want vulkan-loader to depend on mesa during compile-time, since
we couldn't assume that mesa is the only package providing Vulkan drivers.
Thus, it's better for us to export XDG_DATA_DIRS in mesa, so that when both
packages are installed, Vulkan loader could find the corresponding Vulkan
drivers by environment varaible.

---
 gnu/packages/gl.scm | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/gnu/packages/gl.scm b/gnu/packages/gl.scm
index b53b42a9ba..583cd5a945 100644
--- a/gnu/packages/gl.scm
+++ b/gnu/packages/gl.scm
@@ -18,6 +18,7 @@
 ;;; Copyright © 2021, 2022, 2023 John Kehayias <john.kehayias@protonmail.com>
 ;;; Copyright © 2022 Petr Hodina <phodina@protonmail.com>
 ;;; Copyright © 2023 Kaelyn Takata <kaelyn.alexi@protonmail.com>
+;;; Copyright © 2023 dan <i@dan.games>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -518,7 +519,11 @@ (define-public mesa
             ;; Ensure the Mesa VDPAU drivers can be found.
             (variable "VDPAU_DRIVER_PATH")
             (separator #f)
-            (files '("lib/vdpau")))))
+            (files '("lib/vdpau")))
+           (search-path-specification
+            ;; Ensure the Vulkan drivers can be found by Vulkan loader.
+            (variable "XDG_DATA_DIRS")
+            (files '("share")))))
     (home-page "https://mesa3d.org/")
     (synopsis "OpenGL and Vulkan implementations")
     (description "Mesa is a free implementation of the OpenGL and Vulkan

base-commit: 4547bc6fa3142dca77f7fc912368aeff31bd6e53
-- 
2.41.0