mirror of
				https://github.com/python/cpython.git
				synced 2025-10-30 21:21:22 +00:00 
			
		
		
		
	
		
			
				
	
	
		
			193 lines
		
	
	
	
		
			7.2 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			193 lines
		
	
	
	
		
			7.2 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
| #ifndef Py_PYMACRO_H
 | |
| #define Py_PYMACRO_H
 | |
| 
 | |
| // gh-91782: On FreeBSD 12, if the _POSIX_C_SOURCE and _XOPEN_SOURCE macros are
 | |
| // defined, <sys/cdefs.h> disables C11 support and <assert.h> does not define
 | |
| // the static_assert() macro.
 | |
| // https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=255290
 | |
| //
 | |
| // macOS <= 10.10 doesn't define static_assert in assert.h at all despite
 | |
| // having C11 compiler support.
 | |
| //
 | |
| // static_assert is defined in glibc from version 2.16. Compiler support for
 | |
| // the C11 _Static_assert keyword is in gcc >= 4.6.
 | |
| //
 | |
| // MSVC makes static_assert a keyword in C11-17, contrary to the standards.
 | |
| //
 | |
| // In C++11 and C2x, static_assert is a keyword, redefining is undefined
 | |
| // behaviour. So only define if building as C, not C++ (if __cplusplus is
 | |
| // not defined), and only for C11-17.
 | |
| #if !defined(static_assert) && (defined(__GNUC__) || defined(__clang__)) \
 | |
|      && !defined(__cplusplus) && defined(__STDC_VERSION__) \
 | |
|      && __STDC_VERSION__ >= 201112L && __STDC_VERSION__ <= 201710L
 | |
| #  define static_assert _Static_assert
 | |
| #endif
 | |
| 
 | |
| /* Minimum value between x and y */
 | |
| #define Py_MIN(x, y) (((x) > (y)) ? (y) : (x))
 | |
| 
 | |
| /* Maximum value between x and y */
 | |
| #define Py_MAX(x, y) (((x) > (y)) ? (x) : (y))
 | |
| 
 | |
| /* Absolute value of the number x */
 | |
| #define Py_ABS(x) ((x) < 0 ? -(x) : (x))
 | |
| 
 | |
| #define _Py_XSTRINGIFY(x) #x
 | |
| 
 | |
| /* Convert the argument to a string. For example, Py_STRINGIFY(123) is replaced
 | |
|    with "123" by the preprocessor. Defines are also replaced by their value.
 | |
|    For example Py_STRINGIFY(__LINE__) is replaced by the line number, not
 | |
|    by "__LINE__". */
 | |
| #define Py_STRINGIFY(x) _Py_XSTRINGIFY(x)
 | |
| 
 | |
| /* Get the size of a structure member in bytes */
 | |
| #define Py_MEMBER_SIZE(type, member) sizeof(((type *)0)->member)
 | |
| 
 | |
| /* Argument must be a char or an int in [-128, 127] or [0, 255]. */
 | |
| #define Py_CHARMASK(c) ((unsigned char)((c) & 0xff))
 | |
| 
 | |
| #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L \
 | |
|      && !defined(__cplusplus) && !defined(_MSC_VER))
 | |
| #  define Py_BUILD_ASSERT_EXPR(cond) \
 | |
|     ((void)sizeof(struct { int dummy; _Static_assert(cond, #cond); }), \
 | |
|      0)
 | |
| #else
 | |
|    /* Assert a build-time dependency, as an expression.
 | |
|     *
 | |
|     * Your compile will fail if the condition isn't true, or can't be evaluated
 | |
|     * by the compiler. This can be used in an expression: its value is 0.
 | |
|     *
 | |
|     * Example:
 | |
|     *
 | |
|     * #define foo_to_char(foo)  \
 | |
|     *     ((char *)(foo)        \
 | |
|     *      + Py_BUILD_ASSERT_EXPR(offsetof(struct foo, string) == 0))
 | |
|     *
 | |
|     * Written by Rusty Russell, public domain, http://ccodearchive.net/
 | |
|     */
 | |
| #  define Py_BUILD_ASSERT_EXPR(cond) \
 | |
|     (sizeof(char [1 - 2*!(cond)]) - 1)
 | |
| #endif
 | |
| 
 | |
| #if ((defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) \
 | |
|      || (defined(__cplusplus) && __cplusplus >= 201103L))
 | |
|    // Use static_assert() on C11 and newer
 | |
| #  define Py_BUILD_ASSERT(cond) \
 | |
|         do { \
 | |
|             static_assert((cond), #cond); \
 | |
|         } while (0)
 | |
| #else
 | |
| #  define Py_BUILD_ASSERT(cond)  \
 | |
|         do { \
 | |
|             (void)Py_BUILD_ASSERT_EXPR(cond); \
 | |
|         } while(0)
 | |
| #endif
 | |
| 
 | |
| /* Get the number of elements in a visible array
 | |
| 
 | |
|    This does not work on pointers, or arrays declared as [], or function
 | |
|    parameters. With correct compiler support, such usage will cause a build
 | |
|    error (see Py_BUILD_ASSERT_EXPR).
 | |
| 
 | |
|    Written by Rusty Russell, public domain, http://ccodearchive.net/
 | |
| 
 | |
|    Requires at GCC 3.1+ */
 | |
| #if (defined(__GNUC__) && !defined(__STRICT_ANSI__) && \
 | |
|     (((__GNUC__ == 3) && (__GNUC_MINOR__ >= 1)) || (__GNUC__ >= 4)))
 | |
| /* Two gcc extensions.
 | |
|    &a[0] degrades to a pointer: a different type from an array */
 | |
| #define Py_ARRAY_LENGTH(array) \
 | |
|     (sizeof(array) / sizeof((array)[0]) \
 | |
|      + Py_BUILD_ASSERT_EXPR(!__builtin_types_compatible_p(typeof(array), \
 | |
|                                                           typeof(&(array)[0]))))
 | |
| #else
 | |
| #define Py_ARRAY_LENGTH(array) \
 | |
|     (sizeof(array) / sizeof((array)[0]))
 | |
| #endif
 | |
| 
 | |
| 
 | |
| /* Define macros for inline documentation. */
 | |
| #define PyDoc_VAR(name) static const char name[]
 | |
| #define PyDoc_STRVAR(name,str) PyDoc_VAR(name) = PyDoc_STR(str)
 | |
| #ifdef WITH_DOC_STRINGS
 | |
| #define PyDoc_STR(str) str
 | |
| #else
 | |
| #define PyDoc_STR(str) ""
 | |
| #endif
 | |
| 
 | |
| /* Below "a" is a power of 2. */
 | |
| /* Round down size "n" to be a multiple of "a". */
 | |
| #define _Py_SIZE_ROUND_DOWN(n, a) ((size_t)(n) & ~(size_t)((a) - 1))
 | |
| /* Round up size "n" to be a multiple of "a". */
 | |
| #define _Py_SIZE_ROUND_UP(n, a) (((size_t)(n) + \
 | |
|         (size_t)((a) - 1)) & ~(size_t)((a) - 1))
 | |
| /* Round pointer "p" down to the closest "a"-aligned address <= "p". */
 | |
| #define _Py_ALIGN_DOWN(p, a) ((void *)((uintptr_t)(p) & ~(uintptr_t)((a) - 1)))
 | |
| /* Round pointer "p" up to the closest "a"-aligned address >= "p". */
 | |
| #define _Py_ALIGN_UP(p, a) ((void *)(((uintptr_t)(p) + \
 | |
|         (uintptr_t)((a) - 1)) & ~(uintptr_t)((a) - 1)))
 | |
| /* Check if pointer "p" is aligned to "a"-bytes boundary. */
 | |
| #define _Py_IS_ALIGNED(p, a) (!((uintptr_t)(p) & (uintptr_t)((a) - 1)))
 | |
| 
 | |
| /* Use this for unused arguments in a function definition to silence compiler
 | |
|  * warnings. Example:
 | |
|  *
 | |
|  * int func(int a, int Py_UNUSED(b)) { return a; }
 | |
|  */
 | |
| #if defined(__GNUC__) || defined(__clang__)
 | |
| #  define Py_UNUSED(name) _unused_ ## name __attribute__((unused))
 | |
| #elif defined(_MSC_VER)
 | |
|    // Disable warning C4100: unreferenced formal parameter,
 | |
|    // declare the parameter,
 | |
|    // restore old compiler warnings.
 | |
| #  define Py_UNUSED(name) \
 | |
|         __pragma(warning(push)) \
 | |
|         __pragma(warning(suppress: 4100)) \
 | |
|         _unused_ ## name \
 | |
|         __pragma(warning(pop))
 | |
| #else
 | |
| #  define Py_UNUSED(name) _unused_ ## name
 | |
| #endif
 | |
| 
 | |
| #if defined(RANDALL_WAS_HERE)
 | |
| #  define Py_UNREACHABLE() \
 | |
|     Py_FatalError( \
 | |
|         "If you're seeing this, the code is in what I thought was\n" \
 | |
|         "an unreachable state.\n\n" \
 | |
|         "I could give you advice for what to do, but honestly, why\n" \
 | |
|         "should you trust me?  I clearly screwed this up.  I'm writing\n" \
 | |
|         "a message that should never appear, yet I know it will\n" \
 | |
|         "probably appear someday.\n\n" \
 | |
|         "On a deep level, I know I'm not up to this task.\n" \
 | |
|         "I'm so sorry.\n" \
 | |
|         "https://xkcd.com/2200")
 | |
| #elif defined(Py_DEBUG)
 | |
| #  define Py_UNREACHABLE() \
 | |
|     Py_FatalError( \
 | |
|         "We've reached an unreachable state. Anything is possible.\n" \
 | |
|         "The limits were in our heads all along. Follow your dreams.\n" \
 | |
|         "https://xkcd.com/2200")
 | |
| #elif defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5))
 | |
| #  define Py_UNREACHABLE() __builtin_unreachable()
 | |
| #elif defined(__clang__) || defined(__INTEL_COMPILER)
 | |
| #  define Py_UNREACHABLE() __builtin_unreachable()
 | |
| #elif defined(_MSC_VER)
 | |
| #  define Py_UNREACHABLE() __assume(0)
 | |
| #else
 | |
| #  define Py_UNREACHABLE() \
 | |
|     Py_FatalError("Unreachable C code path reached")
 | |
| #endif
 | |
| 
 | |
| #define _Py_CONTAINER_OF(ptr, type, member) \
 | |
|     (type*)((char*)ptr - offsetof(type, member))
 | |
| 
 | |
| // Prevent using an expression as a l-value.
 | |
| // For example, "int x; _Py_RVALUE(x) = 1;" fails with a compiler error.
 | |
| #define _Py_RVALUE(EXPR) ((void)0, (EXPR))
 | |
| 
 | |
| // Return non-zero if the type is signed, return zero if it's unsigned.
 | |
| // Use "<= 0" rather than "< 0" to prevent the compiler warning:
 | |
| // "comparison of unsigned expression in '< 0' is always false".
 | |
| #define _Py_IS_TYPE_SIGNED(type) ((type)(-1) <= 0)
 | |
| 
 | |
| #endif /* Py_PYMACRO_H */
 | 
