Given an aligned type such as:
struct alignas(2048) foo
{
char t[55];
};
I was pleasantly surprised that QVector<foo> provides aligned data (see my
example further, using Qt 5.8 RC)
I could not see this officially mentionned in the Qt documentation.
Yet, this is obviously very useful. Hence, is it a documentation omission, or
"an implementation detail we can't rely on" ?
std::vector does not have this property. As demonstrated with the following
code (this is one example but I tried many)
Tested on VC2015 Update-3 and Clang (XCode 8.1)
qDebug() << sizeof(foo); // gives 2048
QVector<foo> v;
v.resize(10);
qDebug() << intptr_t(v.data()) % sizeof(foo); // gives 0
std::vector<foo> sv;
sv.resize(10);
qDebug() << intptr_t(sv.data()) % sizeof(foo); // gives not 0 (usually)
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