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Diffstat (limited to 'third_party/abseil_cpp/absl/base/internal/inline_variable.h')
| -rw-r--r-- | third_party/abseil_cpp/absl/base/internal/inline_variable.h | 107 |
1 files changed, 0 insertions, 107 deletions
diff --git a/third_party/abseil_cpp/absl/base/internal/inline_variable.h b/third_party/abseil_cpp/absl/base/internal/inline_variable.h deleted file mode 100644 index 130d8c2476..0000000000 --- a/third_party/abseil_cpp/absl/base/internal/inline_variable.h +++ /dev/null @@ -1,107 +0,0 @@ -// Copyright 2017 The Abseil Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// https://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -#ifndef ABSL_BASE_INTERNAL_INLINE_VARIABLE_EMULATION_H_ -#define ABSL_BASE_INTERNAL_INLINE_VARIABLE_EMULATION_H_ - -#include <type_traits> - -#include "absl/base/internal/identity.h" - -// File: -// This file define a macro that allows the creation of or emulation of C++17 -// inline variables based on whether or not the feature is supported. - -//////////////////////////////////////////////////////////////////////////////// -// Macro: ABSL_INTERNAL_INLINE_CONSTEXPR(type, name, init) -// -// Description: -// Expands to the equivalent of an inline constexpr instance of the specified -// `type` and `name`, initialized to the value `init`. If the compiler being -// used is detected as supporting actual inline variables as a language -// feature, then the macro expands to an actual inline variable definition. -// -// Requires: -// `type` is a type that is usable in an extern variable declaration. -// -// Requires: `name` is a valid identifier -// -// Requires: -// `init` is an expression that can be used in the following definition: -// constexpr type name = init; -// -// Usage: -// -// // Equivalent to: `inline constexpr size_t variant_npos = -1;` -// ABSL_INTERNAL_INLINE_CONSTEXPR(size_t, variant_npos, -1); -// -// Differences in implementation: -// For a direct, language-level inline variable, decltype(name) will be the -// type that was specified along with const qualification, whereas for -// emulated inline variables, decltype(name) may be different (in practice -// it will likely be a reference type). -//////////////////////////////////////////////////////////////////////////////// - -#ifdef __cpp_inline_variables - -// Clang's -Wmissing-variable-declarations option erroneously warned that -// inline constexpr objects need to be pre-declared. This has now been fixed, -// but we will need to support this workaround for people building with older -// versions of clang. -// -// Bug: https://bugs.llvm.org/show_bug.cgi?id=35862 -// -// Note: -// identity_t is used here so that the const and name are in the -// appropriate place for pointer types, reference types, function pointer -// types, etc.. -#if defined(__clang__) -#define ABSL_INTERNAL_EXTERN_DECL(type, name) \ - extern const ::absl::internal::identity_t<type> name; -#else // Otherwise, just define the macro to do nothing. -#define ABSL_INTERNAL_EXTERN_DECL(type, name) -#endif // defined(__clang__) - -// See above comment at top of file for details. -#define ABSL_INTERNAL_INLINE_CONSTEXPR(type, name, init) \ - ABSL_INTERNAL_EXTERN_DECL(type, name) \ - inline constexpr ::absl::internal::identity_t<type> name = init - -#else - -// See above comment at top of file for details. -// -// Note: -// identity_t is used here so that the const and name are in the -// appropriate place for pointer types, reference types, function pointer -// types, etc.. -#define ABSL_INTERNAL_INLINE_CONSTEXPR(var_type, name, init) \ - template <class /*AbslInternalDummy*/ = void> \ - struct AbslInternalInlineVariableHolder##name { \ - static constexpr ::absl::internal::identity_t<var_type> kInstance = init; \ - }; \ - \ - template <class AbslInternalDummy> \ - constexpr ::absl::internal::identity_t<var_type> \ - AbslInternalInlineVariableHolder##name<AbslInternalDummy>::kInstance; \ - \ - static constexpr const ::absl::internal::identity_t<var_type>& \ - name = /* NOLINT */ \ - AbslInternalInlineVariableHolder##name<>::kInstance; \ - static_assert(sizeof(void (*)(decltype(name))) != 0, \ - "Silence unused variable warnings.") - -#endif // __cpp_inline_variables - -#endif // ABSL_BASE_INTERNAL_INLINE_VARIABLE_EMULATION_H_ |