1 /* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */ 2 /* 3 * Copyright (c) 1993, 1994, 1995, 1996, 1997 4 * The Regents of the University of California. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by the Computer Systems 17 * Engineering Group at Lawrence Berkeley Laboratory. 18 * 4. Neither the name of the University nor of the Laboratory may be used 19 * to endorse or promote products derived from this software without 20 * specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #ifndef lib_funcattrs_h 36 #define lib_funcattrs_h 37 38 #include "compiler-tests.h" 39 40 /* 41 * Attributes to apply to functions and their arguments, using various 42 * compiler-specific extensions. 43 */ 44 45 /* 46 * NORETURN, before a function declaration, means "this function 47 * never returns". (It must go before the function declaration, e.g. 48 * "extern NORETURN func(...)" rather than after the function 49 * declaration, as the MSVC version has to go before the declaration.) 50 */ 51 #if __has_attribute(noreturn) \ 52 || ND_IS_AT_LEAST_GNUC_VERSION(2,5) \ 53 || ND_IS_AT_LEAST_SUNC_VERSION(5,9) \ 54 || ND_IS_AT_LEAST_XL_C_VERSION(10,1) \ 55 || ND_IS_AT_LEAST_HP_C_VERSION(6,10) \ 56 || __TINYC__ 57 /* 58 * Compiler with support for __attribute((noreturn)), or GCC 2.5 and 59 * later, or some compiler asserting compatibility with GCC 2.5 and 60 * later, or Solaris Studio 12 (Sun C 5.9) and later, or IBM XL C 10.1 61 * and later (do any earlier versions of XL C support this?), or HP aCC 62 * A.06.10 and later, or current TinyCC. 63 */ 64 #define NORETURN __attribute((noreturn)) 65 66 /* 67 * However, GCC didn't support that for function *pointers* until GCC 68 * 4.1.0; see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3481. 69 * 70 * Sun C/Oracle Studio C doesn't seem to support it, either. 71 */ 72 #if (defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) < 401)) \ 73 || (defined(__SUNPRO_C)) 74 #define NORETURN_FUNCPTR 75 #else 76 #define NORETURN_FUNCPTR __attribute((noreturn)) 77 #endif 78 #elif defined(_MSC_VER) 79 /* 80 * MSVC. 81 * It doesn't allow __declspec(noreturn) to be applied to function 82 * pointers. 83 */ 84 #define NORETURN __declspec(noreturn) 85 #define NORETURN_FUNCPTR 86 #else 87 #define NORETURN 88 #define NORETURN_FUNCPTR 89 #endif 90 91 /* 92 * WARN_UNUSED_RESULT, before a function declaration, means "the caller 93 * should use the result of this function" (even if it's just a success/ 94 * failure indication). 95 */ 96 #if __has_attribute(warn_unused_result) \ 97 || ND_IS_AT_LEAST_GNUC_VERSION(3,4) \ 98 || ND_IS_AT_LEAST_HP_C_VERSION(6,25) 99 #define WARN_UNUSED_RESULT __attribute((warn_unused_result)) 100 #else 101 #define WARN_UNUSED_RESULT 102 #endif 103 104 /* 105 * PRINTFLIKE(x,y), after a function declaration, means "this function 106 * does printf-style formatting, with the xth argument being the format 107 * string and the yth argument being the first argument for the format 108 * string". 109 */ 110 #if __has_attribute(__format__) \ 111 || ND_IS_AT_LEAST_GNUC_VERSION(2,3) \ 112 || ND_IS_AT_LEAST_XL_C_VERSION(10,1) \ 113 || ND_IS_AT_LEAST_HP_C_VERSION(6,10) 114 /* 115 * Compiler with support for it, or GCC 2.3 and later, or some compiler 116 * asserting compatibility with GCC 2.3 and later, or IBM XL C 10.1 117 * and later (do any earlier versions of XL C support this?), 118 * or HP aCC A.06.10 and later. 119 */ 120 #define PRINTFLIKE(x,y) __attribute__((__format__(__printf__,x,y))) 121 122 /* 123 * However, GCC didn't support that for function *pointers* until GCC 124 * 4.1.0; see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3481. 125 * XL C 16.1 (and possibly some earlier versions, but not 12.1 or 13.1) has 126 * a similar bug, the bugfix for which was made in: 127 * * version 16.1.1.8 for Linux (25 June 2020), which fixes 128 * https://www.ibm.com/support/pages/apar/LI81402 129 * * version 16.1.0.5 for AIX (5 May 2020), which fixes 130 * https://www.ibm.com/support/pages/apar/IJ24678 131 * 132 * When testing versions, keep in mind that XL C 16.1 pretends to be both 133 * GCC 4.2 and Clang 4.0 at once. 134 */ 135 #if (ND_IS_AT_LEAST_GNUC_VERSION(4,1) \ 136 && !ND_IS_AT_LEAST_XL_C_VERSION(10,1)) \ 137 || (ND_IS_AT_LEAST_XL_C_VERSION(16,1) \ 138 && (ND_IS_AT_LEAST_XL_C_MODFIX(1, 8) && defined(__linux__)) \ 139 || (ND_IS_AT_LEAST_XL_C_MODFIX(0, 5) && defined(_AIX))) 140 #define PRINTFLIKE_FUNCPTR(x,y) __attribute__((__format__(__printf__,x,y))) 141 #endif 142 #endif 143 144 #if !defined(PRINTFLIKE) 145 #define PRINTFLIKE(x,y) 146 #endif 147 #if !defined(PRINTFLIKE_FUNCPTR) 148 #define PRINTFLIKE_FUNCPTR(x,y) 149 #endif 150 151 /* 152 * For flagging arguments as format strings in MSVC. 153 */ 154 #ifdef _MSC_VER 155 #include <sal.h> 156 #define FORMAT_STRING(p) _Printf_format_string_ p 157 #else 158 #define FORMAT_STRING(p) p 159 #endif 160 161 #endif /* lib_funcattrs_h */ 162