diff --git a/std/io.zig b/std/io.zig
index 92de108661..c42cb294d9 100644
--- a/std/io.zig
+++ b/std/io.zig
@@ -1,6 +1,6 @@
 const system = switch(@compileVar("os")) {
-    linux => @import("linux.zig"),
-    darwin => @import("darwin.zig"),
+    Os.linux => @import("linux.zig"),
+    Os.darwin => @import("darwin.zig"),
     else => @compileError("Unsupported OS"),
 };
 
diff --git a/std/math.zig b/std/math.zig
index b44a4d5def..acc9eaec73 100644
--- a/std/math.zig
+++ b/std/math.zig
@@ -12,7 +12,7 @@ pub fn max(x: var, y: var) -> @typeOf(x + y) {
     if (x > y) x else y
 }
 
-pub error Overflow;
+error Overflow;
 pub fn mulOverflow(inline T: type, a: T, b: T) -> %T {
     var answer: T = undefined;
     if (@mulWithOverflow(T, a, b, &answer)) error.Overflow else answer