From f4bac3ca173be9f219099c04e76d6d62c4d0e19e Mon Sep 17 00:00:00 2001 From: Giuseppe D'Angelo Date: Thu, 21 Mar 2024 10:48:05 +0100 Subject: [PATCH] QTypeInfo: add detection for Clang's __is_trivially_relocatable Types marked with [[clang::trivial_abi]] are considered to be trivially relocatable for Clang. This is ABI compatible, since in Qt 6 we can change the value of QTypeInfo::IsRelocatable "after the fact" -- it simply means that code that doesn't get recompiled is pessimized. Change-Id: I32e52bfb212c7919b2ebcf7832ede4404358330f Reviewed-by: Thiago Macieira --- src/corelib/global/qtypeinfo.h | 8 +++++++- tests/auto/corelib/global/qglobal/tst_qglobal.cpp | 14 ++++++++++++++ 2 files changed, 21 insertions(+), 1 deletion(-) diff --git a/src/corelib/global/qtypeinfo.h b/src/corelib/global/qtypeinfo.h index 9b2119da1df..473854f230c 100644 --- a/src/corelib/global/qtypeinfo.h +++ b/src/corelib/global/qtypeinfo.h @@ -23,7 +23,13 @@ class QDebug; namespace QtPrivate { template -inline constexpr bool qIsRelocatable = std::is_trivially_copyable_v && std::is_trivially_destructible_v; +inline constexpr bool qIsRelocatable = (std::is_trivially_copyable_v && std::is_trivially_destructible_v) +#if defined(__has_builtin) +#if __has_builtin(__is_trivially_relocatable) + || __is_trivially_relocatable(T) +#endif +#endif + ; // Denotes types that are trivially default constructible, and for which // value-initialization can be achieved by filling their storage with 0 bits. diff --git a/tests/auto/corelib/global/qglobal/tst_qglobal.cpp b/tests/auto/corelib/global/qglobal/tst_qglobal.cpp index 1a19048bbe7..524212e9333 100644 --- a/tests/auto/corelib/global/qglobal/tst_qglobal.cpp +++ b/tests/auto/corelib/global/qglobal/tst_qglobal.cpp @@ -930,6 +930,20 @@ struct Trivial1 static_assert(!QTypeInfo::isComplex); static_assert(QTypeInfo::isRelocatable); +#if defined(__has_builtin) +#if __has_builtin(__is_trivially_relocatable) && __has_attribute(trivial_abi) +struct [[clang::trivial_abi]] TrivialAbi1 +{ + ~TrivialAbi1(); + TrivialAbi1(TrivialAbi1 &&); +}; +static_assert(__has_builtin(__is_trivially_relocatable)); +static_assert(__is_trivially_relocatable(TrivialAbi1)); +static_assert(QTypeInfo::isComplex); +static_assert(QTypeInfo::isRelocatable); +#endif +#endif + QT_END_NAMESPACE QTEST_APPLESS_MAIN(tst_QGlobal)