diff options
Diffstat (limited to 'include/llvm/Support/Compiler.h')
| -rw-r--r-- | include/llvm/Support/Compiler.h | 81 |
1 files changed, 47 insertions, 34 deletions
diff --git a/include/llvm/Support/Compiler.h b/include/llvm/Support/Compiler.h index 3f4f465f3960..cb7e57d4cd21 100644 --- a/include/llvm/Support/Compiler.h +++ b/include/llvm/Support/Compiler.h @@ -7,7 +7,8 @@ //===----------------------------------------------------------------------===// // // This file defines several macros, based on the current compiler. This allows -// use of compiler-specific features in a way that remains portable. +// use of compiler-specific features in a way that remains portable. This header +// can be included from either C or C++. // //===----------------------------------------------------------------------===// @@ -16,7 +17,9 @@ #include "llvm/Config/llvm-config.h" +#ifdef __cplusplus #include <new> +#endif #include <stddef.h> #if defined(_MSC_VER) @@ -35,14 +38,20 @@ # define __has_attribute(x) 0 #endif -#ifndef __has_cpp_attribute -# define __has_cpp_attribute(x) 0 -#endif - #ifndef __has_builtin # define __has_builtin(x) 0 #endif +// Only use __has_cpp_attribute in C++ mode. GCC defines __has_cpp_attribute in +// C mode, but the :: in __has_cpp_attribute(scoped::attribute) is invalid. +#ifndef LLVM_HAS_CPP_ATTRIBUTE +#if defined(__cplusplus) && defined(__has_cpp_attribute) +# define LLVM_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x) +#else +# define LLVM_HAS_CPP_ATTRIBUTE(x) 0 +#endif +#endif + /// \macro LLVM_GNUC_PREREQ /// Extend the default __GNUC_PREREQ even if glibc's features.h isn't /// available. @@ -62,13 +71,21 @@ /// \macro LLVM_MSC_PREREQ /// Is the compiler MSVC of at least the specified version? /// The common \param version values to check for are: -/// * 1900: Microsoft Visual Studio 2015 / 14.0 +/// * 1910: VS2017, version 15.1 & 15.2 +/// * 1911: VS2017, version 15.3 & 15.4 +/// * 1912: VS2017, version 15.5 +/// * 1913: VS2017, version 15.6 +/// * 1914: VS2017, version 15.7 +/// * 1915: VS2017, version 15.8 +/// * 1916: VS2017, version 15.9 +/// * 1920: VS2019, version 16.0 +/// * 1921: VS2019, version 16.1 #ifdef _MSC_VER #define LLVM_MSC_PREREQ(version) (_MSC_VER >= (version)) -// We require at least MSVC 2015. -#if !LLVM_MSC_PREREQ(1900) -#error LLVM requires at least MSVC 2015. +// We require at least MSVC 2017. +#if !LLVM_MSC_PREREQ(1910) +#error LLVM requires at least MSVC 2017. #endif #else @@ -120,14 +137,18 @@ #endif /// LLVM_NODISCARD - Warn if a type or return value is discarded. -#if __cplusplus > 201402L && __has_cpp_attribute(nodiscard) + +// Use the 'nodiscard' attribute in C++17 or newer mode. +#if __cplusplus > 201402L && LLVM_HAS_CPP_ATTRIBUTE(nodiscard) #define LLVM_NODISCARD [[nodiscard]] -#elif !__cplusplus -// Workaround for llvm.org/PR23435, since clang 3.6 and below emit a spurious -// error when __has_cpp_attribute is given a scoped attribute in C mode. -#define LLVM_NODISCARD -#elif __has_cpp_attribute(clang::warn_unused_result) +#elif LLVM_HAS_CPP_ATTRIBUTE(clang::warn_unused_result) #define LLVM_NODISCARD [[clang::warn_unused_result]] +// Clang in C++14 mode claims that it has the 'nodiscard' attribute, but also +// warns in the pedantic mode that 'nodiscard' is a C++17 extension (PR33518). +// Use the 'nodiscard' attribute in C++14 mode only with GCC. +// TODO: remove this workaround when PR33518 is resolved. +#elif defined(__GNUC__) && LLVM_HAS_CPP_ATTRIBUTE(nodiscard) +#define LLVM_NODISCARD [[nodiscard]] #else #define LLVM_NODISCARD #endif @@ -139,7 +160,7 @@ // The clang-tidy check bugprone-use-after-move recognizes this attribute as a // marker that a moved-from object has left the indeterminate state and can be // reused. -#if __has_cpp_attribute(clang::reinitializes) +#if LLVM_HAS_CPP_ATTRIBUTE(clang::reinitializes) #define LLVM_ATTRIBUTE_REINITIALIZES [[clang::reinitializes]] #else #define LLVM_ATTRIBUTE_REINITIALIZES @@ -240,15 +261,13 @@ #endif /// LLVM_FALLTHROUGH - Mark fallthrough cases in switch statements. -#if __cplusplus > 201402L && __has_cpp_attribute(fallthrough) +#if __cplusplus > 201402L && LLVM_HAS_CPP_ATTRIBUTE(fallthrough) #define LLVM_FALLTHROUGH [[fallthrough]] -#elif __has_cpp_attribute(gnu::fallthrough) +#elif LLVM_HAS_CPP_ATTRIBUTE(gnu::fallthrough) #define LLVM_FALLTHROUGH [[gnu::fallthrough]] -#elif !__cplusplus -// Workaround for llvm.org/PR23435, since clang 3.6 and below emit a spurious -// error when __has_cpp_attribute is given a scoped attribute in C mode. -#define LLVM_FALLTHROUGH -#elif __has_cpp_attribute(clang::fallthrough) +#elif __has_attribute(fallthrough) +#define LLVM_FALLTHROUGH __attribute__((fallthrough)) +#elif LLVM_HAS_CPP_ATTRIBUTE(clang::fallthrough) #define LLVM_FALLTHROUGH [[clang::fallthrough]] #else #define LLVM_FALLTHROUGH @@ -256,7 +275,7 @@ /// LLVM_REQUIRE_CONSTANT_INITIALIZATION - Apply this to globals to ensure that /// they are constant initialized. -#if __has_cpp_attribute(clang::require_constant_initialization) +#if LLVM_HAS_CPP_ATTRIBUTE(clang::require_constant_initialization) #define LLVM_REQUIRE_CONSTANT_INITIALIZATION \ [[clang::require_constant_initialization]] #else @@ -338,14 +357,6 @@ # define LLVM_ASSUME_ALIGNED(p, a) (p) #endif -/// \macro LLVM_ALIGNAS -/// Used to specify a minimum alignment for a structure or variable. -#if __GNUC__ && !__has_feature(cxx_alignas) && !LLVM_GNUC_PREREQ(4, 8, 1) -# define LLVM_ALIGNAS(x) __attribute__((aligned(x))) -#else -# define LLVM_ALIGNAS(x) alignas(x) -#endif - /// \macro LLVM_PACKED /// Used to specify a packed structure. /// LLVM_PACKED( @@ -376,8 +387,8 @@ /// \macro LLVM_PTR_SIZE /// A constant integer equivalent to the value of sizeof(void*). -/// Generally used in combination with LLVM_ALIGNAS or when doing computation in -/// the preprocessor. +/// Generally used in combination with alignas or when doing computation in the +/// preprocessor. #ifdef __SIZEOF_POINTER__ # define LLVM_PTR_SIZE __SIZEOF_POINTER__ #elif defined(_WIN64) @@ -527,6 +538,7 @@ void AnnotateIgnoreWritesEnd(const char *file, int line); #define LLVM_ENABLE_EXCEPTIONS 1 #endif +#ifdef __cplusplus namespace llvm { /// Allocate a buffer of memory with the given size and alignment. @@ -569,4 +581,5 @@ inline void deallocate_buffer(void *Ptr, size_t Size, size_t Alignment) { } // End namespace llvm +#endif // __cplusplus #endif |