From 6156a541452dbb0178c7759be1533a5eb94e0b7e Mon Sep 17 00:00:00 2001
From: david gauchard <gauchard@laas.fr>
Date: Tue, 16 Apr 2019 20:29:50 +0200
Subject: [PATCH] polledTimeout: ensures timeType is unsigned (#5991)

---
 cores/esp8266/PolledTimeout.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/cores/esp8266/PolledTimeout.h b/cores/esp8266/PolledTimeout.h
index 91bebaa79..95157d377 100644
--- a/cores/esp8266/PolledTimeout.h
+++ b/cores/esp8266/PolledTimeout.h
@@ -142,6 +142,7 @@ class timeoutTemplate
 {
 public:
   using timeType = typename TimePolicyT::timeType;
+  static_assert(std::is_unsigned<timeType>::value == true, "timeType must be unsigned");
 
   static constexpr timeType alwaysExpired   = 0;
   static constexpr timeType neverExpires    = std::numeric_limits<timeType>::max();