added missing header
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>
