gnu: Add go-github-com-ianlancetaylor-demangle.

* gnu/packages/golang-xyz.scm (go-github-com-ianlancetaylor-demangle):
New variable.

Signed-off-by: Sharlatan Hellseher <sharlatanus@gmail.com>
Change-Id: I3db163b9d32eff30539d81556309ec554bc3dbe6

gnu/packages/golang-xyz.scm

@@ -1491,6 +1491,34 @@ (define-public go-github-com-josharian-intern
 called concurrently with themselves and each other.")
     (license license:expat)))
 
+(define-public go-github-com-ianlancetaylor-demangle
+  ;; No release, see <https://github.com/ianlancetaylor/demangle/issues/21>.
+  (package
+    (name "go-github-com-ianlancetaylor-demangle")
+    (version "0.0.0-20230524184225-eabc099b10ab")
+    (source
+     (origin
+       (method git-fetch)
+       (uri (git-reference
+             (url "https://github.com/ianlancetaylor/demangle")
+             (commit (go-version->git-ref version))))
+       (file-name (git-file-name name version))
+       (sha256
+        (base32 "1pvlg1adp50hnw8dz7il473xb197ixirg26cy5hj3ngb4qlajwvc"))))
+    (build-system go-build-system)
+    (arguments
+     (list
+      #:import-path "github.com/ianlancetaylor/demangle"))
+    (home-page "https://github.com/ianlancetaylor/demangle")
+    (synopsis "Symbol name demangler written in Go")
+    (description
+     "This package defines functions that demangle GCC/LLVM C++ and Rust
+symbol names.  This package recognizes names that were mangled according to
+the C++ ABI defined at https://codesourcery.com/cxx-abi/ and the
+@url{https://rust-lang.github.io/rfcs/2603-rust-symbol-name-mangling-v0.html,Rust
+ABI}.")
+    (license license:bsd-3)))
+
 (define-public go-github-com-k0kubun-pp
   (package
     (name "go-github-com-k0kubun-pp")