Fix windows build, add release target

flake.nix

@@ -38,7 +38,13 @@
         "x86_64-windows" = newBuildTarget {
           nixPkgsSystem = "x86_64-w64-mingw32";
           rustTarget = "x86_64-pc-windows-gnu";
-          nativeBuildInputs = pkgsCross: [ pkgsCross.windows.pthreads ];
+          nativeBuildInputs = pkgsCross: [
+            pkgsCross.stdenv.cc
+            pkgsCross.windows.pthreads
+          ];
+          rustFlags = pkgsCross: [
+            "-C" "link-arg=-L${pkgsCross.windows.pthreads}/lib"
+          ];
         };
       };
 
@@ -62,12 +68,29 @@
       # "$system.cross-$system" for every system.
       #
       eachCrossSystem = supportedSystems: callback:
-        eachSystem supportedSystems (buildSystem: builtins.foldl'
+        eachSystem supportedSystems (buildSystem: let
+          pkgs = mkPkgs buildSystem null;
+          crosses = builtins.foldl'
             (inner: targetSystem: inner // {
               "cross-${targetSystem}" = callback buildSystem targetSystem;
             })
             { default = callback buildSystem buildSystem; }
-            supportedSystems
+            supportedSystems;
+        in
+          crosses // (rec {
+            default = callback buildSystem buildSystem;
+            release = let
+              bins = pkgs.symlinkJoin {
+                name = "${default.name}-all-bins";
+                paths = builtins.attrValues crosses;
+              };
+            in
+              pkgs.runCommand "${default.name}-release" {} ''
+                cp -rL "${bins}" "$out"
+                chmod +w "$out"/bin
+                (cd "$out"/bin && sha256sum * > sha256.txt)
+              '';
+          })
         );
 
       mkPkgs = buildSystem: targetSystem: import nixpkgs ({
@@ -82,20 +105,9 @@
       }));
 
       mkToolchain = buildSystem: targetSystem: let
-        debug = v: builtins.trace v v;
         buildTarget = buildTargets.${targetSystem};
         rustTarget = buildTarget.rustTarget;
-        #fenixPkgs = fenix.packages.${buildSystem};
-
-        # TODO prefer to use the nix flake fenix
-        fenixPkgs = import ((mkPkgs buildSystem null).fetchFromGitHub {
-          owner = "nix-community";
-          repo = "fenix";
-          rev = "81ab0b4f7ae9ebb57daa0edf119c4891806e4d3a";
-          hash = "sha256-bZmI7ytPAYLpyFNgj5xirDkKuAniOkj1xHdv5aIJ5GM=";
-        }) {
-          system = buildSystem;
-        };
+        fenixPkgs = fenix.packages.${buildSystem};
 
         # TODO I'd prefer to use the toolchain file
         # https://github.com/nix-community/fenix/issues/123
@@ -145,7 +157,7 @@
 
             # https://github.com/rust-lang/cargo/issues/4133
             "-C" "linker=${TARGET_CC}"
-          ];
+          ] ++ (buildTarget.rustFlags pkgsCross);
         };
 
     in {
@@ -165,6 +177,17 @@
             strictDeps = true;
             doCheck = false;
             release = true;
+            postInstall = ''
+              cd "$out"/bin
+              for f in "$(ls)"; do
+                if ext="$(echo "$f" | grep -oP '\.[a-z]+$')"; then
+                  base="$(echo "$f" | cut -d. -f1)"
+                  mv "$f" "$base-${targetSystem}$ext"
+                else
+                  mv "$f" "$f-${targetSystem}"
+                fi
+              done
+            '';
           } // (buildEnv buildSystem targetSystem))
         );