1 // Copyright 2017 The Abseil Authors. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // https://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 // 15 // ----------------------------------------------------------------------------- 16 // File: policy_checks.h 17 // ----------------------------------------------------------------------------- 18 // 19 // This header enforces a minimum set of policies at build time, such as the 20 // supported compiler and library versions. Unsupported configurations are 21 // reported with `#error`. This enforcement is best effort, so successfully 22 // compiling this header does not guarantee a supported configuration. 23 24 #ifndef ABSL_BASE_POLICY_CHECKS_H_ 25 #define ABSL_BASE_POLICY_CHECKS_H_ 26 27 // Included for the __GLIBC_PREREQ macro used below. 28 #include <limits.h> 29 30 // Included for the _STLPORT_VERSION macro used below. 31 #if defined(__cplusplus) 32 #include <cstddef> 33 #endif 34 35 // ----------------------------------------------------------------------------- 36 // Operating System Check 37 // ----------------------------------------------------------------------------- 38 39 #if defined(__CYGWIN__) 40 #error "Cygwin is not supported." 41 #endif 42 43 // ----------------------------------------------------------------------------- 44 // Toolchain Check 45 // ----------------------------------------------------------------------------- 46 47 // We support Visual Studio 2019 (MSVC++ 16.0) and later. 48 // This minimum will go up. 49 #if defined(_MSC_VER) && _MSC_VER < 1920 && !defined(__clang__) 50 #error "This package requires Visual Studio 2019 (MSVC++ 16.0) or higher." 51 #endif 52 53 // We support GCC 7 and later. 54 // This minimum will go up. 55 #if defined(__GNUC__) && !defined(__clang__) 56 #if __GNUC__ < 7 57 #error "This package requires GCC 7 or higher." 58 #endif 59 #endif 60 61 // We support Apple Xcode clang 4.2.1 (version 421.11.65) and later. 62 // This corresponds to Apple Xcode version 4.5. 63 // This minimum will go up. 64 #if defined(__apple_build_version__) && __apple_build_version__ < 4211165 65 #error "This package requires __apple_build_version__ of 4211165 or higher." 66 #endif 67 68 // ----------------------------------------------------------------------------- 69 // C++ Version Check 70 // ----------------------------------------------------------------------------- 71 72 // Enforce C++14 as the minimum. 73 #if defined(_MSVC_LANG) 74 #if _MSVC_LANG < 201402L 75 #error "C++ versions less than C++14 are not supported." 76 #endif // _MSVC_LANG < 201402L 77 #elif defined(__cplusplus) 78 #if __cplusplus < 201402L 79 #error "C++ versions less than C++14 are not supported." 80 #endif // __cplusplus < 201402L 81 #endif 82 83 // ----------------------------------------------------------------------------- 84 // Standard Library Check 85 // ----------------------------------------------------------------------------- 86 87 #if defined(_STLPORT_VERSION) 88 #error "STLPort is not supported." 89 #endif 90 91 // ----------------------------------------------------------------------------- 92 // `char` Size Check 93 // ----------------------------------------------------------------------------- 94 95 // Abseil currently assumes CHAR_BIT == 8. If you would like to use Abseil on a 96 // platform where this is not the case, please provide us with the details about 97 // your platform so we can consider relaxing this requirement. 98 #if CHAR_BIT != 8 99 #error "Abseil assumes CHAR_BIT == 8." 100 #endif 101 102 // ----------------------------------------------------------------------------- 103 // `int` Size Check 104 // ----------------------------------------------------------------------------- 105 106 // Abseil currently assumes that an int is 4 bytes. If you would like to use 107 // Abseil on a platform where this is not the case, please provide us with the 108 // details about your platform so we can consider relaxing this requirement. 109 #if INT_MAX < 2147483647 110 #error "Abseil assumes that int is at least 4 bytes. " 111 #endif 112 113 #endif // ABSL_BASE_POLICY_CHECKS_H_ 114