diff options
| author | Marc Mutz <marc.mutz@qt.io> | 2023-05-31 19:33:10 +0200 |
|---|---|---|
| committer | Marc Mutz <marc.mutz@qt.io> | 2023-07-13 07:50:25 +0000 |
| commit | 0ecf8a21587e33c5c5b554d5bc059488001c8990 (patch) | |
| tree | 12ad9cdca591efd99656461db5fecdc5ab3e86d6 | |
| parent | 93fe8cb305791ab0099831361ff1634a047dd13f (diff) | |
QVariant: make customConstructShared() SCARY¹
Extract Method non-template customConstructSharedImpl() to avoid
instantiating std::unique_ptr with a different per-F Deleter over and
over again.
Not picking to 6.5 because the function was confined to the
qvariant.cpp TU in those versions.
Cf. 11791e2a50417661679f84aeae21ce959cab638f and
d783363f60173f1bc6525f1a8bbbd87f1e3afc1d for similar issues.
¹ https://www.open-std.org/jtc1/sc22/WG21/docs/papers/2009/n2911.pdf
Pick-to: 6.6
Change-Id: I73d21d929a7db2ab47f62a3246cf913d82e3db75
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
| -rw-r--r-- | src/corelib/kernel/qvariant_p.h | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/src/corelib/kernel/qvariant_p.h b/src/corelib/kernel/qvariant_p.h index fef43dab03..d2a7390938 100644 --- a/src/corelib/kernel/qvariant_p.h +++ b/src/corelib/kernel/qvariant_p.h @@ -19,8 +19,7 @@ QT_BEGIN_NAMESPACE -template <typename F> static QVariant::PrivateShared * -customConstructShared(size_t size, size_t align, F &&construct) +inline auto customConstructSharedImpl(size_t size, size_t align) { struct Deleter { void operator()(QVariant::PrivateShared *p) const @@ -30,6 +29,13 @@ customConstructShared(size_t size, size_t align, F &&construct) // this is exception-safe std::unique_ptr<QVariant::PrivateShared, Deleter> ptr; ptr.reset(QVariant::PrivateShared::create(size, align)); + return ptr; +} + +template <typename F> static QVariant::PrivateShared * +customConstructShared(size_t size, size_t align, F &&construct) +{ + auto ptr = customConstructSharedImpl(size, align); construct(ptr->data()); return ptr.release(); } |