Add clang 21 compiler tests to CI

Signed-off-by: Matthias J. Kannwischer <[email protected]>

Author: mkannwischer

.github/workflows/ci.yml

@@ -52,6 +52,9 @@ jobs:
          - name: clang-20
            shell: ci_clang20
            darwin: True
+         - name: clang-21
+           shell: ci_clang21
+           darwin: True
          # CPU flags are not correctly passed to the zig assembler
          # https://github.com/ziglang/zig/issues/23576
          # We therefore only test the C backend

flake.lock

@@ -52,6 +52,7 @@
                 gcc48 = pkgs-2405.gcc48;
                 gcc49 = pkgs-2405.gcc49;
                 gcc7 = pkgs-2405.gcc7;
+                clang_21 = pkgs-unstable.clang_21;
               })
             ];
           };
@@ -115,6 +116,7 @@
           devShells.ci_clang18 = util.mkShellWithCC' pkgs.clang_18;
           devShells.ci_clang19 = util.mkShellWithCC' pkgs.clang_19;
           devShells.ci_clang20 = util.mkShellWithCC' pkgs.clang_20;
+          devShells.ci_clang21 = util.mkShellWithCC' pkgs.clang_21;
 
           devShells.ci_zig0_12 = util.mkShellWithCC' (zigWrapCC pkgs.zig_0_12);
           devShells.ci_zig0_13 = util.mkShellWithCC' (zigWrapCC pkgs.zig_0_13);