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Why does GCC generate such radically different assembly for nearly the same C code?
...oesn't answer the most important question, "Why does GCC generate such radically different assembly".)
– orlp
Apr 20 '12 at 18:24
...
Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
...omewhat faster than sqrtss.
edit: If speed is critical, and you're really calling this in a loop for many values, you should be using the vectorized versions of these instructions, rsqrtps or sqrtps, both of which process four floats per instruction.
...
How to declare std::unique_ptr and what is the use of it?
... way.
Smart pointers are supposed to model object ownership, and automatically take care of destroying the pointed object when the last (smart, owning) pointer to that object falls out of scope.
This way you do not have to remember doing delete on objects allocated dynamically - the destructor o...
ASP.NET Repeater bind List
...t null values you may want to refactor to this (.NET 6+)
<asp:Repeater ID="repeater" runat="server">
<ItemTemplate>
<%# Container.DataItem?.ToString() ?? string.Empty%>
</ItemTemplate>
</asp:Repeater>
Note if you are using less than .NET 6 you cannot ...
Do I need to explicitly call the base virtual destructor?
... the destructor again as virtual on the inheriting class, but do I need to call the base destructor?
7 Answers
...
Where do “pure virtual function call” crashes come from?
... programs that crash on my computer with the error: "pure virtual function call".
8 Answers
...
How to add a new method to a php object on the fly?
...
You can harness __call for this:
class Foo
{
public function __call($method, $args)
{
if (isset($this->$method)) {
$func = $this->$method;
return call_user_func_array($func, $args);
}
...
Check if a row exists, otherwise insert
...row for each flight? If so:
IF EXISTS (SELECT * FROM Bookings WHERE FLightID = @Id)
BEGIN
--UPDATE HERE
END
ELSE
BEGIN
-- INSERT HERE
END
I assume what I said, as your way of doing things can overbook a flight, as it will insert a new row when there are 10 tickets max and you are booking 2...
How do you post to an iframe?
...some clever ninja hack; although it was deprecated (and therefore won't validate) in HTML 4 Strict or XHTML 1 Strict, it's been part of HTML since 3.2, it's formally part of HTML5, and it works in just about every browser since Netscape 3.
I have verified this behaviour as working with XHTML 1 Stri...
How do I detect a click outside an element?
...completely when a user clicks on the head of these menus. I would like to hide these elements when the user clicks outside the menus' area.
...