diff --git a/Package.swift b/Package.swift
index 5d45950db..f02ef1828 100644
--- a/Package.swift
+++ b/Package.swift
@@ -7,7 +7,7 @@ let availabilityDefinition = PackageDescription.SwiftSetting.unsafeFlags([
     "-Xfrontend",
     "-define-availability",
     "-Xfrontend",
-    "SwiftStdlib 5.7:macOS 9999, iOS 9999, watchOS 9999, tvOS 9999",
+    "SwiftStdlib 5.7:macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0",
     "-Xfrontend",
     "-define-availability",
     "-Xfrontend",
diff --git a/Sources/_StringProcessing/Engine/Processor.swift b/Sources/_StringProcessing/Engine/Processor.swift
index 18e355fb5..ed84cc6db 100644
--- a/Sources/_StringProcessing/Engine/Processor.swift
+++ b/Sources/_StringProcessing/Engine/Processor.swift
@@ -91,6 +91,8 @@ struct Processor {
   var isTracingEnabled: Bool
   let shouldMeasureMetrics: Bool
   var metrics: ProcessorMetrics = ProcessorMetrics()
+
+  let fastUTF8: UnsafeRawBufferPointer? = nil
 }
 
 extension Processor {