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Edit File: pymacro.h
#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 (if __STDC_VERSION__ is defined), // not C++, and only for C11-17. #if !defined(static_assert) && (defined(__GNUC__) || defined(__clang__)) \ && 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)) /* 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) #define Py_BUILD_ASSERT(cond) do { \ (void)Py_BUILD_ASSERT_EXPR(cond); \ } while(0) /* 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)) #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 // 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)) #endif /* Py_PYMACRO_H */