diff --git a/changelog.md b/changelog.md
index 0bb285c..8b18482 100644
--- a/changelog.md
+++ b/changelog.md
@@ -33,6 +33,8 @@ HEAD
   a build error. It wasn't being used for anything particularly important
   (slightly improving error reporting) and there isn't a great replacement.
   #599 Thank you Gianfranco Costamagna for reporting.
+- Compatibility: Add missing `<stdint>` headers. Fixes issues with g++ 5.4.0.
+  #638 Thank you Alex Korotkin for reporting and a patch.
 - Bug: Store loggers in shared pointers to avoid crashes related to connections
   trying to write logs entries after their respective endpoint has been
   deallocated. Thank you Thalhammer for reporting and Jupp Müller for the 
diff --git a/websocketpp/extensions/permessage_deflate/disabled.hpp b/websocketpp/extensions/permessage_deflate/disabled.hpp
index 49c0e1d..6573095 100644
--- a/websocketpp/extensions/permessage_deflate/disabled.hpp
+++ b/websocketpp/extensions/permessage_deflate/disabled.hpp
@@ -29,6 +29,7 @@
 #define WEBSOCKETPP_EXTENSION_PERMESSAGE_DEFLATE_DISABLED_HPP
 
 #include <websocketpp/common/cpp11.hpp>
+#include <websocketpp/common/stdint.hpp>
 #include <websocketpp/common/system_error.hpp>
 
 #include <websocketpp/http/constants.hpp>
diff --git a/websocketpp/extensions/permessage_deflate/enabled.hpp b/websocketpp/extensions/permessage_deflate/enabled.hpp
index f20a1b1..563b954 100644
--- a/websocketpp/extensions/permessage_deflate/enabled.hpp
+++ b/websocketpp/extensions/permessage_deflate/enabled.hpp
@@ -32,6 +32,7 @@
 #include <websocketpp/common/cpp11.hpp>
 #include <websocketpp/common/memory.hpp>
 #include <websocketpp/common/platforms.hpp>
+#include <websocketpp/common/stdint.hpp>
 #include <websocketpp/common/system_error.hpp>
 #include <websocketpp/error.hpp>
 
diff --git a/websocketpp/uri.hpp b/websocketpp/uri.hpp
index 7159234..c0b8b0c 100644
--- a/websocketpp/uri.hpp
+++ b/websocketpp/uri.hpp
@@ -31,6 +31,7 @@
 #include <websocketpp/error.hpp>
 
 #include <websocketpp/common/memory.hpp>
+#include <websocketpp/common/stdint.hpp>
 
 #include <algorithm>
 #include <sstream>