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How much is the overhead of smart pointers compared to normal pointers in C++?
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shared_ptr has a significant overhead for creation because of it's memory allocation for the control block (which keeps the ref counter and a pointer list to all weak references). It has also a huge memory overhead because of this and the fact that std::shared_ptr is always a 2 pointer tuple (one t...
MySQL maximum memory usage
...5-8 so called important settings. First off, not all of them matter - e.g. allocating a lot of resources to InnoDB and not using InnoDB doesn't make a lot of sense because those resources are wasted.
Or - a lot of people suggest to up the max_connection variable -- well, little do they know it also...
Can I use Objective-C blocks as properties?
... @CharlieMonroe - Yes you are probably right, but dont you need a dealloc implementation to nil or release the block property without ARC? (its been a while since I used non-ARC)
– Robert
Mar 31 '13 at 21:58
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What does string::npos mean in this code?
...rison with string::npos might not work.
size_type, which is defined by the allocator of the string, must be an unsigned
integral type. The default allocator, allocator, uses type size_t as size_type. Because -1 is
converted into an unsigned integral type, npos is the maximum unsigned value of its ty...
How do I use a custom deleter with a std::unique_ptr member?
...d up with UB if the pointer passed into std::unique_ptr<Bar> was not allocated from create(), but from some other allocation function.
– Justin
Jul 10 '18 at 20:18
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C compile error: “Variable-sized object may not be initialized”
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I can use for this purpose malloc as well, what about the second question, I wrote it after Pavel's reply
– helloWorld
Jun 21 '10 at 8:10
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Does free(ptr) where ptr is NULL corrupt memory?
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The free function causes the space pointed to by ptr to be deallocated, that is, made
available for further allocation. If ptr is a null pointer, no action occurs.
See ISO-IEC 9899.
That being said, when looking at different codebases in the wild, you'll notice people sometimes d...
Customize UITableView header section
...ew viewForHeaderInSection:(NSInteger)section
{
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, tableView.frame.size.width, 18)];
/* Create custom view to display section header... */
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(10, 5, tableView.frame.size.widt...
Determine if running on a rooted device
...ss is being created on every launch of application. At first these zombies allocate 0KB but than something happens and zombie processes are holding nearly same KBs as my application's main process and they became standart processes.
There is a bug report for same issue on bugs.sun.com: http://bugs....
My attempt at value initialization is interpreted as a function declaration, and why doesn't A a(())
...or: initializing argument 1 of ‘std::basic_string<_CharT, _Traits, _Alloc>::basic_string(const _CharT*, const _Alloc&) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]’ [-fpermissive]
basic_string<_CharT, _Traits, _Alloc>::
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