1 files changed, 42 insertions, 0 deletions
diff --git a/contrib/llvm-project/clang/lib/Headers/stdckdint.h b/contrib/llvm-project/clang/lib/Headers/stdckdint.h
new file mode 100644
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+++ b/contrib/llvm-project/clang/lib/Headers/stdckdint.h
@@ -0,0 +1,42 @@
+/*===---- stdckdint.h - Standard header for checking integer----------------===
+ *
+ * Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+ * See https://llvm.org/LICENSE.txt for license information.
+ * SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+ *
+ *===-----------------------------------------------------------------------===
+ */
+
+#ifndef __STDCKDINT_H
+#define __STDCKDINT_H
+
+/* If we're hosted, fall back to the system's stdckdint.h. FreeBSD, for
+ * example, already has a Clang-compatible stdckdint.h header.
+ *
+ * The `stdckdint.h` header requires C 23 or newer.
+ */
+#if __STDC_HOSTED__ && __has_include_next(<stdckdint.h>)
+#include_next <stdckdint.h>
+#else
+
+/* C23 7.20.1 Defines several macros for performing checked integer arithmetic*/
+
+#define __STDC_VERSION_STDCKDINT_H__ 202311L
+
+// Both A and B shall be any integer type other than "plain" char, bool, a bit-
+// precise integer type, or an enumerated type, and they need not be the same.
+
+// R shall be a modifiable lvalue of any integer type other than "plain" char,
+// bool, a bit-precise integer type, or an enumerated type. It shouldn't be
+// short type, either. Otherwise, it may be unable to hold two the result of
+// operating two 'int's.
+
+// A diagnostic message will be produced if A or B are not suitable integer
+// types, or if R is not a modifiable lvalue of a suitable integer type or R
+// is short type.
+#define ckd_add(R, A, B) __builtin_add_overflow((A), (B), (R))
+#define ckd_sub(R, A, B) __builtin_sub_overflow((A), (B), (R))
+#define ckd_mul(R, A, B) __builtin_mul_overflow((A), (B), (R))
+
+#endif /* __STDC_HOSTED__ */
+#endif /* __STDCKDINT_H */