Do not CpuScalingEnabled on Windows.
diff --git a/src/sysinfo.cc b/src/sysinfo.cc
index a0199a3..a4e791a 100644
--- a/src/sysinfo.cc
+++ b/src/sysinfo.cc
@@ -394,6 +394,7 @@
        : nullptr)
 
 bool CpuScalingEnabled() {
+#ifndef OS_WINDOWS
   // On Linux, the CPUfreq subsystem exposes CPU information as files on the
   // local file system. If reading the exported files fails, then we may not be
   // running on Linux, so we silently ignore all the read errors.
@@ -407,6 +408,7 @@
     fclose(file);
     if (memprefix(buff, bytes_read, "performance") == nullptr) return true;
   }
+#endif
   return false;
 }