diff --git a/src/compiler/perfLogger.ts b/src/compiler/perfLogger.ts index 974e231d15d4b..5696a97ad423d 100644 --- a/src/compiler/perfLogger.ts +++ b/src/compiler/perfLogger.ts @@ -36,8 +36,8 @@ namespace ts { etwModule = undefined; } - /** Performance logger that will generate ETW events if possible */ - export const perfLogger: PerfLogger = etwModule ? etwModule : nullLogger; + /** Performance logger that will generate ETW events if possible - check for `logEvent` member, as `etwModule` will be `{}` when browserified */ + export const perfLogger: PerfLogger = etwModule && etwModule.logEvent ? etwModule : nullLogger; perfLogger.logInfoEvent(`Starting TypeScript v${versionMajorMinor} with command line: ${JSON.stringify(process.argv)}`); }