Switching "host" configurations to "exec" (#449)

bindgen/bindgen.bzl

@@ -197,27 +197,27 @@ rust_bindgen_toolchain = rule(
         "bindgen": attr.label(
             doc = "The label of a `bindgen` executable.",
             executable = True,
-            cfg = "host",
+            cfg = "exec",
         ),
         "rustfmt": attr.label(
             doc = "The label of a `rustfmt` executable. If this is provided, generated sources will be formatted.",
             executable = True,
-            cfg = "host",
+            cfg = "exec",
             mandatory = False,
         ),
         "clang": attr.label(
             doc = "The label of a `clang` executable.",
             executable = True,
-            cfg = "host",
+            cfg = "exec",
         ),
         "libclang": attr.label(
             doc = "A cc_library that provides bindgen's runtime dependency on libclang.",
-            cfg = "host",
+            cfg = "exec",
             providers = [CcInfo],
         ),
         "libstdcxx": attr.label(
             doc = "A cc_library that satisfies libclang's libstdc++ dependency.",
-            cfg = "host",
+            cfg = "exec",
             providers = [CcInfo],
         ),
     },

cargo/cargo_build_script.bzl

@@ -147,7 +147,7 @@ _build_script_run = rule(
             executable = True,
             allow_files = True,
             mandatory = True,
-            cfg = "host",
+            cfg = "exec",
         ),
         "crate_name": attr.string(
             doc = "Name of the crate associated with this build script target",
@@ -171,7 +171,7 @@ _build_script_run = rule(
             executable = True,
             allow_files = True,
             default = Label("//cargo/cargo_build_script_runner:cargo_build_script_runner"),
-            cfg = "host",
+            cfg = "exec",
         ),
     },
     fragments = ["cpp"],

proto/proto.bzl

@@ -293,7 +293,7 @@ rust_proto_library = rule(
         ),
         "_optional_output_wrapper": attr.label(
             executable = True,
-            cfg = "host",
+            cfg = "exec",
             default = Label(
                 "@io_bazel_rules_rust//proto:optional_output_wrapper",
             ),
@@ -372,7 +372,7 @@ rust_grpc_library = rule(
         ),
         "_optional_output_wrapper": attr.label(
             executable = True,
-            cfg = "host",
+            cfg = "exec",
             default = Label(
                 "@io_bazel_rules_rust//proto:optional_output_wrapper",
             ),

proto/toolchain.bzl

@@ -130,21 +130,21 @@ rust_proto_toolchain = rule(
         "protoc": attr.label(
             doc = "The location of the `protoc` binary. It should be an executable target.",
             executable = True,
-            cfg = "host",
+            cfg = "exec",
             default = Label("@com_google_protobuf//:protoc"),
         ),
         "proto_plugin": attr.label(
             doc = "The location of the Rust protobuf compiler plugin used to generate rust sources.",
             allow_single_file = True,
-            cfg = "host",
+            cfg = "exec",
             default = Label(
                 "@io_bazel_rules_rust//proto:protoc_gen_rust",
             ),
         ),
         "grpc_plugin": attr.label(
             doc = "The location of the Rust protobuf compiler plugin to generate rust gRPC stubs.",
             allow_single_file = True,
-            cfg = "host",
+            cfg = "exec",
             default = Label(
                 "@io_bazel_rules_rust//proto:protoc_gen_rust_grpc",
             ),

wasm_bindgen/wasm_bindgen.bzl

@@ -109,7 +109,7 @@ rust_wasm_bindgen_toolchain = rule(
         "bindgen": attr.label(
             doc = "The label of a `bindgen` executable.",
             executable = True,
-            cfg = "host",
+            cfg = "exec",
         ),
     },
 )