diff --git a/PlaygroundLogger/PlaygroundLogger/Common.swift b/PlaygroundLogger/PlaygroundLogger/Common.swift
index 29f97ec..c39b3c5 100644
--- a/PlaygroundLogger/PlaygroundLogger/Common.swift
+++ b/PlaygroundLogger/PlaygroundLogger/Common.swift
@@ -67,7 +67,7 @@ func boundCheckRanges(_ ranges : [ChildrenRange], _ upper_bound : UInt64) -> [Ch
     return actual_ranges
 }
 
-extension Integer where Self.Stride: SignedInteger {
+extension FixedWidthInteger where Self.Stride: SignedInteger {
     func doFor (f: (Self) -> ()) {
         for x in CountableRange(uncheckedBounds: (lower: 0 as Self, upper:self)) {
             f(x)
diff --git a/PlaygroundLogger/PlaygroundLogger/LoggerMirror.swift b/PlaygroundLogger/PlaygroundLogger/LoggerMirror.swift
index 2970187..bf2c0c6 100644
--- a/PlaygroundLogger/PlaygroundLogger/LoggerMirror.swift
+++ b/PlaygroundLogger/PlaygroundLogger/LoggerMirror.swift
@@ -50,7 +50,7 @@ final class LoggerMirror {
     
     var count: Int {
         let direct_count = self.mirror.children.count
-        let base_count = (nil == self.superclass ? 0 : 1)
+        let base_count: Int64 = (nil == self.superclass ? 0 : 1)
         return Int(direct_count+base_count)
     }