gnu: Add gdb-12.

* gnu/packages/gdb.scm (gdb-12): New variable.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

gnu/packages/gdb.scm

@@ -149,6 +149,18 @@ the program is running to try to fix bugs.  It can be used to debug programs
 written in C, C++, Ada, Objective-C, Pascal and more.")
     (license gpl3+)))
 
+(define-public gdb-12
+  (package
+    (inherit gdb-11)
+    (version "12.1")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append "mirror://gnu/gdb/gdb-"
+                                  version ".tar.xz"))
+              (sha256
+               (base32
+                "1vczsqcbh5y0gx7qrclpna0qzx26sk7lra6y8qzxam1biyzr65qf"))))))
+
 (define-public gdb
   ;; This is the fixed version that packages depend on.  Update it rarely
   ;; enough to avoid massive rebuilds.