-/*
- * Get an aligned pointer to a value. This is meant
- * as a helper to pass an aligned pointer to a member in a packed structure
- * to a function.
- */
-#define ALIGNED_CONST_PTR(value) (((const typeof(value) []) { value }))
+/* Attribute suitable to tag functions as having printf()-like arguments. */
+#define ATTR_FORMAT_PRINTF(_string_index, _first_to_check) \
+ __attribute__((format(printf, _string_index, _first_to_check)))
+
+/* Attribute suitable to tag functions as having strftime()-like arguments. */
+#define ATTR_FORMAT_STRFTIME(_string_index) \
+ __attribute__((format(strftime, _string_index, 0)))
+
+/* Macros used to ignore specific compiler diagnostics. */
+
+#define DIAGNOSTIC_PUSH _Pragma("GCC diagnostic push")
+#define DIAGNOSTIC_POP _Pragma("GCC diagnostic pop")
+
+#if defined(__clang__)
+ /* Clang */
+# define DIAGNOSTIC_IGNORE_SUGGEST_ATTRIBUTE_FORMAT
+# define DIAGNOSTIC_IGNORE_FORMAT_NONLITERAL \
+ _Pragma("GCC diagnostic ignored \"-Wformat-nonliteral\"")
+# define DIAGNOSTIC_IGNORE_LOGICAL_OP
+#else
+ /* GCC */
+# define DIAGNOSTIC_IGNORE_SUGGEST_ATTRIBUTE_FORMAT \
+ _Pragma("GCC diagnostic ignored \"-Wsuggest-attribute=format\"")
+# define DIAGNOSTIC_IGNORE_FORMAT_NONLITERAL \
+ _Pragma("GCC diagnostic ignored \"-Wformat-nonliteral\"")
+# define DIAGNOSTIC_IGNORE_LOGICAL_OP \
+ _Pragma("GCC diagnostic ignored \"-Wlogical-op\"")
+#endif
+
+/* Used to make specific C++ functions to C code. */
+#ifdef __cplusplus
+#define C_LINKAGE extern "C"
+#else
+#define C_LINKAGE
+#endif