diff --git a/src/json.hpp b/src/json.hpp
index d6a3d6a..23c4554 100644
--- a/src/json.hpp
+++ b/src/json.hpp
@@ -33,6 +33,7 @@
 #include <array>
 #include <cassert>
 #include <ciso646>
+#include <climits>
 #include <cmath>
 #include <cstddef>
 #include <cstdint>
@@ -77,8 +78,6 @@
     #endif
 #endif
 
-#undef COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW
-
 // select or define functions for unsigned integer arithmetic
 #ifdef COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW
     #define add_and_check_overflow(a,b,res,overflow) { overflow = __builtin_uaddll_overflow(a, b, &res); }
diff --git a/src/json.hpp.re2c b/src/json.hpp.re2c
index be05565..bf9366c 100644
--- a/src/json.hpp.re2c
+++ b/src/json.hpp.re2c
@@ -33,6 +33,7 @@
 #include <array>
 #include <cassert>
 #include <ciso646>
+#include <climits>
 #include <cmath>
 #include <cstddef>
 #include <cstdint>