1 From 32d07c1ed42529efeb0664d4232bc5c94eedb6a9 Mon Sep 17 00:00:00 2001 2 From: Andrew Hsieh <andrewhsieh (a] google.com> 3 Date: Sun, 27 Apr 2014 22:19:17 -0700 4 Subject: [PATCH 06/12] Emulate __has_feature() for GCC 5 6 __config defines dozens of _LIBCPP_* flags based on the compiler support of 7 language features: for clang it uses __has_feature() to discover; for gcc most 8 flags are hard-coded based on gcc version. Unfortunately some code in libc++ 9 still use __has_features() directly instead of _LIBCPP_* flags. This CL emulates 10 __has_feature() for GCC (from the default "0") 11 --- 12 include/__config | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 13 1 file changed, 60 insertions(+) 14 15 diff --git a/include/__config b/include/__config 16 index 64519b7..df84ac6 100644 17 --- a/include/__config 18 +++ b/include/__config 19 @@ -434,6 +434,66 @@ using namespace _LIBCPP_NAMESPACE __attribute__((__strong__)); 20 #define _LIBCPP_HAS_NO_ASAN 21 #endif 22 23 +// Emulation of clang's __has_feature() for GCC on known cases 24 +#ifndef __has_feature 25 + 26 +#define __gxx__cxx_access_control_sfinae !defined(_LIBCPP_HAS_NO_TRAILING_RETURN) || !defined(_LIBCPP_HAS_NO_ADVANCED_SFINAE) // Also see usage in 7 tests 27 +#define __gxx__cxx_alias_templates !defined(_LIBCPP_HAS_NO_TEMPLATE_ALIASES) 28 +#define __gxx__cxx_address_sanitizer !defined(_LIBCPP_HAS_NO_ASAN) 29 +#define __gxx__cxx_alignas 0 // Not sure, doesn't matter. 30 +#define __gxx__cxx_atomic 0 // (_GNUC_VER >= 409) seems to support _Atomic in -std=c11 not -std=c++11 ! 31 +#define __gxx__cxx_attributes 0 // Not sure. Also see usage in libcxx/test/utilities/meta/meta.unary/meta.unary.prop/is_polymorphic.pass.cpp 32 +#define __gxx__cxx_auto_type !defined(_LIBCPP_HAS_NO_AUTO_TYPE) 33 +#define __gxx__cxx_constexpr !defined(_LIBCPP_HAS_NO_CONSTEXPR) 34 +#define __gxx__cxx_decltype !defined(_LIBCPP_HAS_NO_DECLTYPE) 35 +#define __gxx__cxx_defaulted_functions !defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) // libcxx/test/utilities/meta/meta.unary/meta.unary.prop/is_trivially_move_constructible.pass.cpp 36 +#define __gxx__cxx_deleted_functions !defined(_LIBCPP_HAS_NO_DELETED_FUNCTIONS) 37 +#define __gxx__cxx_exceptions !defined(_LIBCPP_NO_EXCEPTIONS) 38 +#define __gxx__cxx_explicit_conversions (_GNUC_VER >= 405) 39 +#define __gxx__cxx_generalized_initializers !defined(_LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS) 40 +#define __gxx__cxx_lambdas !defined(_LIBCPP_HAS_NO_LAMBDAS) 41 +#define __gxx__cxx_noexcept 0 // Not sure, doesn't matter. 42 +#define __gxx__cxx_nullptr !defined(_LIBCPP_HAS_NO_NULLPTR) 43 +#define __gxx__cxx_reference_qualified_functions (_GNUC_VER >= 408) // Not if 4.7 work. 4.6 certainly not. Also see usage in libcxx/include/type_traits 44 +#ifdef _LIBCPP_NO_RTTI 45 +#define __gxx__cxx_rtti 0 46 +#else 47 +#define __gxx__cxx_rtti __GXX_RTTI 48 +#endif 49 +#define __gxx__cxx_rvalue_references !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) 50 +#define __gxx__cxx_static_assert !defined(_LIBCPP_HAS_NO_STATIC_ASSERT) 51 +#define __gxx__cxx_strong_enums !defined(_LIBCPP_HAS_NO_STRONG_ENUMS) // See usage in libcxx/test/utilities/meta/meta.trans/meta.trans.other/underlying_type.pass.cpp 52 +#define __gxx__cxx_trailing_return !defined(_LIBCPP_HAS_NO_TRAILING_RETURN) 53 +#define __gxx__cxx_unrestricted_unions 1 // Not sure. Also See usage in libcxx/test/utilities/meta/meta.unary/meta.unary.prop/is_nothrow_destructible.pass.cpp 54 +#define __gxx__cxx_variadic_templates !defined(_LIBCPP_HAS_NO_VARIADICS) 55 +#define __gxx__has_nothrow_assign (_GNUC_VER >= 403) // See usage in libcxx/include/type_traits 56 +#define __gxx__has_nothrow_constructor (_GNUC_VER >= 403) // See usage in libcxx/include/type_traits 57 +#define __gxx__has_nothrow_copy (_GNUC_VER >= 403) // See usage in libcxx/include/type_traits 58 +#define __gxx__has_trivial_constructor (_GNUC_VER >= 403) // See usage in libcxx/include/type_traits 59 +#define __gxx__has_trivial_destructor (_GNUC_VER >= 403) // See usage in libcxx/include/type_traits 60 +#define __gxx__has_virtual_destructor (_GNUC_VER >= 403) // See usage in libcxx/include/type_traits 61 +#define __gxx__is_base_of !defined(_LIBCPP_HAS_IS_BASE_OF) // See usage in libcxx/include/type_traits 62 +#define __gxx__is_class (_GNUC_VER >= 403) // See usage in libcxx/include/type_traits 63 +#define __gxx__is_convertible_to 0 // Not supported in GCC 4.8. Also see usage in libcxx/include/type_traits 64 +#define __gxx__is_empty 1 // Not sure. Also see usage in libcxx/include/type_traits 65 +#define __gxx__is_enum (_GNUC_VER >= 403) // See usage in libcxx/include/type_traits 66 +#define __gxx__is_final (_GNUC_VER >= 408) // Not if 4.7 work. 4.6 certainly not. Also see usage in libcxx/include/unordered_map,tuple,ext/hash_map,map,memory 67 +#define __gxx__is_literal 0 // Not supported in GCC 4.8. Also see usage in libcxx/include/type_traits 68 +#define __gxx__is_pod (_GNUC_VER >= 403) // See usage in libcxx/include/type_traits 69 +#define __gxx__is_polymorphic 1 // Not sure. Also see usage in libcxx/include/type_traits 70 +#define __gxx__is_standard_layout 1 // Not sure. Also see usage in libcxx/include/type_traits 71 +#define __gxx__is_trivial 0 // Not supported in GCC 4.8. Also see usage in libcxx/include/type_traits 72 +#define __gxx__is_trivially_constructible 0 // Not supported in GCC 4.8. Also see usage in libcxx/include/type_traits 73 +#define __gxx__is_trivially_copyable 0 // Not supported in GCC 4.8. Also see usage in libcxx/include/type_traits 74 +#define __gxx__is_union (_GNUC_VER >= 403) // See usage in libcxx/include/type_traits 75 +#define __gxx__objc_arc defined(_LIBCPP_HAS_OBJC_ARC) 76 +#define __gxx__objc_arc_weak defined(_LIBCPP_HAS_OBJC_ARC_WEAK) 77 +#define __gxx__underlying_type 1 // Not sure. Also see usage in libcxx/include/type_traits 78 + 79 +#define __has_feature(__x) __gxx__ ## __x 80 + 81 +#endif // __has_feature 82 + 83 #elif defined(_LIBCPP_MSVC) 84 85 #define _LIBCPP_HAS_NO_TEMPLATE_ALIASES 86 -- 87 1.9.1.423.g4596e3a 88 89
