--- /dev/null
+/*
+ LUFA Library
+ Copyright (C) Dean Camera, 2017.
+
+ dean [at] fourwalledcubicle [dot] com
+ www.lufa-lib.org
+*/
+
+/*
+ Copyright 2017 Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+ Permission to use, copy, modify, distribute, and sell this
+ software and its documentation for any purpose is hereby granted
+ without fee, provided that the above copyright notice appear in
+ all copies and that both that the copyright notice and this
+ permission notice and warranty disclaimer appear in supporting
+ documentation, and that the name of the author not be used in
+ advertising or publicity pertaining to distribution of the
+ software without specific, written prior permission.
+
+ The author disclaims all warranties with regard to this
+ software, including all implied warranties of merchantability
+ and fitness. In no event shall the author be liable for any
+ special, indirect or consequential damages or any damages
+ whatsoever resulting from loss of use, data or profits, whether
+ in an action of contract, negligence or other tortious action,
+ arising out of or in connection with the use or performance of
+ this software.
+*/
+
+/** \file
+ * \brief Special function/variable attribute macros.
+ *
+ * \copydetails Group_FuncVarAttributes
+ *
+ * \note Do not include this file directly, rather include the Common.h header file instead to gain this file's
+ * functionality.
+ */
+
+/** \ingroup Group_Common
+ * \defgroup Group_FuncVarAttributes Function/Variable Attributes
+ * \brief Special function/variable attribute macros.
+ *
+ * This module contains macros for applying specific attributes to functions and variables to control various
+ * optimizer and code generation features of the compiler. Attributes may be placed in the function prototype
+ * or variable declaration in any order, and multiple attributes can be specified for a single item via a space
+ * separated list.
+ *
+ * On incompatible versions of GCC or on other compilers, these macros evaluate to nothing unless they are
+ * critical to the code's function and thus must throw a compile error when used.
+ *
+ * @{
+ */
+
+#ifndef __LUFA_ATTR_H__
+#define __LUFA_ATTR_H__
+
+ /* Preprocessor Checks: */
+ #if !defined(__INCLUDE_FROM_COMMON_H)
+ #error Do not include this file directly. Include LUFA/Common/Common.h instead to gain this functionality.
+ #endif
+
+ /* Public Interface - May be used in end-application: */
+ /* Macros: */
+ #if (__GNUC__ >= 3) || defined(__DOXYGEN__)
+ /** Indicates to the compiler that the function can not ever return, so that any stack restoring or
+ * return code may be omitted by the compiler in the resulting binary.
+ */
+ #define ATTR_NO_RETURN __attribute__ ((noreturn))
+
+ /** Indicates that the function returns a value which should not be ignored by the user code. When
+ * applied, any ignored return value from calling the function will produce a compiler warning.
+ */
+ #define ATTR_WARN_UNUSED_RESULT __attribute__ ((warn_unused_result))
+
+ /** Indicates that the specified parameters of the function are pointers which should never be \c NULL.
+ * When applied as a 1-based comma separated list the compiler will emit a warning if the specified
+ * parameters are known at compiler time to be \c NULL at the point of calling the function.
+ */
+ #define ATTR_NON_NULL_PTR_ARG(...) __attribute__ ((nonnull (__VA_ARGS__)))
+
+ /** Removes any preamble or postamble from the function. When used, the function will not have any
+ * register or stack saving code. This should be used with caution, and when used the programmer
+ * is responsible for maintaining stack and register integrity.
+ */
+ #define ATTR_NAKED __attribute__ ((naked))
+
+ /** Prevents the compiler from considering a specified function for in-lining. When applied, the given
+ * function will not be in-lined under any circumstances.
+ */
+ #define ATTR_NO_INLINE __attribute__ ((noinline))
+
+ /** Forces the compiler to inline the specified function. When applied, the given function will be
+ * in-lined under all circumstances.
+ */
+ #define ATTR_ALWAYS_INLINE __attribute__ ((always_inline))
+
+ /** Indicates that the specified function is pure, in that it has no side-effects other than global
+ * or parameter variable access.
+ */
+ #define ATTR_PURE __attribute__ ((pure))
+
+ /** Indicates that the specified function is constant, in that it has no side effects other than
+ * parameter access.
+ */
+ #define ATTR_CONST __attribute__ ((const))
+
+ /** Marks a given function as deprecated, which produces a warning if the function is called. */
+ #define ATTR_DEPRECATED __attribute__ ((deprecated))
+
+ /** Marks a function as a weak reference, which can be overridden by other functions with an
+ * identical name (in which case the weak reference is discarded at link time).
+ */
+ #define ATTR_WEAK __attribute__ ((weak))
+ #endif
+
+ /** Forces the compiler to not automatically zero the given global variable on startup, so that the
+ * current RAM contents is retained. Under most conditions this value will be random due to the
+ * behavior of volatile memory once power is removed, but may be used in some specific circumstances,
+ * like the passing of values back after a system watchdog reset.
+ */
+ #define ATTR_NO_INIT __attribute__ ((section (".noinit")))
+
+ /** Places the function in one of the initialization sections, which execute before the main function
+ * of the application. Refer to the avr-libc manual for more information on the initialization sections.
+ *
+ * \param[in] SectionIndex Initialization section number where the function should be placed.
+ */
+ #define ATTR_INIT_SECTION(SectionIndex) __attribute__ ((used, naked, section (".init" #SectionIndex )))
+
+ /** Marks a function as an alias for another function.
+ *
+ * \param[in] Func Name of the function which the given function name should alias.
+ */
+ #define ATTR_ALIAS(Func) __attribute__ ((alias( #Func )))
+
+ /** Marks a variable or struct element for packing into the smallest space available, omitting any
+ * alignment bytes usually added between fields to optimize field accesses.
+ */
+ #define ATTR_PACKED __attribute__ ((packed))
+
+ /** Indicates the minimum alignment in bytes for a variable or struct element.
+ *
+ * \param[in] Bytes Minimum number of bytes the item should be aligned to.
+ */
+ #define ATTR_ALIGNED(Bytes) __attribute__ ((aligned(Bytes)))
+#endif
+
+/** @} */
+
projects / qmk_firmware.git / blobdiff