1 // Copyright 2013 The Flutter Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef FLUTTER_FML_COMPILER_SPECIFIC_H_ 6 #define FLUTTER_FML_COMPILER_SPECIFIC_H_ 7 8 #if !defined(__GNUC__) && !defined(__clang__) && !defined(_MSC_VER) 9 #error Unsupported compiler. 10 #endif 11 12 // Annotate a variable indicating it's ok if the variable is not used. 13 // (Typically used to silence a compiler warning when the assignment 14 // is important for some other reason.) 15 // Use like: 16 // int x = ...; 17 // FML_ALLOW_UNUSED_LOCAL(x); 18 #define FML_ALLOW_UNUSED_LOCAL(x) false ? (void)x : (void)0 19 20 // Annotate a typedef or function indicating it's ok if it's not used. 21 // Use like: 22 // typedef Foo Bar ALLOW_UNUSED_TYPE; 23 #if defined(__GNUC__) || defined(__clang__) 24 #define FML_ALLOW_UNUSED_TYPE __attribute__((unused)) 25 #else 26 #define FML_ALLOW_UNUSED_TYPE 27 #endif 28 29 // Annotate a function indicating it should not be inlined. 30 // Use like: 31 // NOINLINE void DoStuff() { ... } 32 #if defined(__GNUC__) || defined(__clang__) 33 #define FML_NOINLINE __attribute__((noinline)) 34 #elif defined(_MSC_VER) 35 #define FML_NOINLINE __declspec(noinline) 36 #endif 37 38 // Specify memory alignment for structs, classes, etc. 39 // Use like: 40 // class FML_ALIGNAS(16) MyClass { ... } 41 // FML_ALIGNAS(16) int array[4]; 42 #if defined(__GNUC__) || defined(__clang__) 43 #define FML_ALIGNAS(byte_alignment) __attribute__((aligned(byte_alignment))) 44 #elif defined(_MSC_VER) 45 #define FML_ALIGNAS(byte_alignment) __declspec(align(byte_alignment)) 46 #endif 47 48 // Return the byte alignment of the given type (available at compile time). 49 // Use like: 50 // FML_ALIGNOF(int32) // this would be 4 51 #if defined(__GNUC__) || defined(__clang__) 52 #define FML_ALIGNOF(type) __alignof__(type) 53 #elif defined(_MSC_VER) 54 #define FML_ALIGNOF(type) __alignof(type) 55 #endif 56 57 // Annotate a function indicating the caller must examine the return value. 58 // Use like: 59 // int foo() FML_WARN_UNUSED_RESULT; 60 // To explicitly ignore a result, see |ignore_result()| in base/macros.h. 61 #if defined(__GNUC__) || defined(__clang__) 62 #define FML_WARN_UNUSED_RESULT __attribute__((warn_unused_result)) 63 #else 64 #define FML_WARN_UNUSED_RESULT 65 #endif 66 67 // Tell the compiler a function is using a printf-style format string. 68 // |format_param| is the one-based index of the format string parameter; 69 // |dots_param| is the one-based index of the "..." parameter. 70 // For v*printf functions (which take a va_list), pass 0 for dots_param. 71 // (This is undocumented but matches what the system C headers do.) 72 #if defined(__GNUC__) || defined(__clang__) 73 #define FML_PRINTF_FORMAT(format_param, dots_param) \ 74 __attribute__((format(printf, format_param, dots_param))) 75 #else 76 #define FML_PRINTF_FORMAT(format_param, dots_param) 77 #endif 78 79 #endif // FLUTTER_FML_COMPILER_SPECIFIC_H_ 80