Upgrade RunResponse.exit_code to int64

POSIX allows returning values that span all of int. This means that on
ILP64 systems, int32 is not necessarily large enough to fit all possible
exit codes.

pkg/builder/local_build_executor.go

@@ -299,7 +299,7 @@ func (be *localBuildExecutor) Execute(ctx context.Context, filePool re_filesyste
 
 	// Attach the exit code or execution error.
 	if runErr == nil {
-		response.Result.ExitCode = runResponse.ExitCode
+		response.Result.ExitCode = int32(runResponse.ExitCode)
 		response.Result.ExecutionMetadata.AuxiliaryMetadata = append(response.Result.ExecutionMetadata.AuxiliaryMetadata, runResponse.ResourceUsage...)
 	} else {
 		attachErrorToExecuteResponse(response, util.StatusWrap(runErr, "Failed to run command"))

pkg/proto/runner/runner.proto

@@ -62,7 +62,7 @@ message RunRequest {
 
 message RunResponse {
   // Exit code generated by the process.
-  int32 exit_code = 1;
+  int64 exit_code = 1;
 
   // Runner-specific information on the amount of resources used during
   // execution.

pkg/runner/local_runner.go

@@ -212,7 +212,7 @@ func (r *localRunner) Run(ctx context.Context, request *runner.RunRequest) (*run
 		return nil, util.StatusWrap(err, "Failed to marshal POSIX resource usage")
 	}
 	return &runner.RunResponse{
-		ExitCode:      int32(cmd.ProcessState.ExitCode()),
+		ExitCode:      int64(cmd.ProcessState.ExitCode()),
 		ResourceUsage: []*anypb.Any{posixResourceUsage},
 	}, nil
 }

pkg/runner/local_runner_test.go

@@ -124,7 +124,7 @@ func TestLocalRunnerRun(t *testing.T) {
 			TemporaryDirectory: "EmptyEnvironment/tmp",
 		})
 		require.NoError(t, err)
-		require.Equal(t, int32(0), response.ExitCode)
+		require.Equal(t, int64(0), response.ExitCode)
 
 		stdout, err := os.ReadFile(filepath.Join(testPath, "stdout"))
 		require.NoError(t, err)
@@ -158,7 +158,7 @@ func TestLocalRunnerRun(t *testing.T) {
 			TemporaryDirectory: "NonEmptyEnvironment/tmp",
 		})
 		require.NoError(t, err)
-		require.Equal(t, int32(0), response.ExitCode)
+		require.Equal(t, int64(0), response.ExitCode)
 
 		stdout, err := os.ReadFile(filepath.Join(testPath, "stdout"))
 		require.NoError(t, err)
@@ -213,7 +213,7 @@ func TestLocalRunnerRun(t *testing.T) {
 			TemporaryDirectory:   "OverridingTmpdir/tmp",
 		})
 		require.NoError(t, err)
-		require.Equal(t, int32(0), response.ExitCode)
+		require.Equal(t, int64(0), response.ExitCode)
 
 		stdout, err := os.ReadFile(filepath.Join(testPath, "stdout"))
 		require.NoError(t, err)
@@ -256,7 +256,7 @@ func TestLocalRunnerRun(t *testing.T) {
 			TemporaryDirectory: "NonZeroExitCode/tmp",
 		})
 		require.NoError(t, err)
-		require.Equal(t, int32(255), response.ExitCode)
+		require.Equal(t, int64(255), response.ExitCode)
 
 		stdout, err := os.ReadFile(filepath.Join(testPath, "stdout"))
 		require.NoError(t, err)
@@ -289,7 +289,7 @@ func TestLocalRunnerRun(t *testing.T) {
 			TemporaryDirectory: "SigKill/tmp",
 		})
 		require.NoError(t, err)
-		require.NotEqual(t, int32(0), response.ExitCode)
+		require.NotEqual(t, int64(0), response.ExitCode)
 
 		require.Len(t, response.ResourceUsage, 1)
 		var posixResourceUsage resourceusage.POSIXResourceUsage
@@ -372,7 +372,7 @@ func TestLocalRunnerRun(t *testing.T) {
 			TemporaryDirectory:   "RelativeSearchPath/tmp",
 		})
 		require.NoError(t, err)
-		require.Equal(t, int32(42), response.ExitCode)
+		require.Equal(t, int64(42), response.ExitCode)
 
 		stdout, err := os.ReadFile(filepath.Join(testPath, "stdout"))
 		require.NoError(t, err)