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diff --git a/src/support/stdckdint.h b/src/support/stdckdint.h
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+++ b/src/support/stdckdint.h
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+/*
+ * Copyright 2024 WebAssembly Community Group participants
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef wasm_stdckdint_h
+#define wasm_stdckdint_h
+
+// This is a partial "polyfill" for the C23 file stdckdint.h. It allows us to
+// use that API even in older compilers.
+
+namespace std {
+
+template<typename T> bool ckd_add(T* output, T a, T b) {
+#if __has_builtin(__builtin_add_overflow)
+  return __builtin_add_overflow(a, b, output);
+#else
+  // Atm this polyfill only supports unsigned types.
+  static_assert(std::is_unsigned_v<T>);
+
+  T result = a + b;
+  if (result < a) {
+    return true;
+  }
+  *output = result;
+  return false;
+#endif
+}
+
+} // namespace std
+
+#endif // wasm_stdckdint_h