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Difference in make_shared and normal shared_ptr in C++
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The difference is that std::make_shared performs one heap-allocation, whereas calling the std::shared_ptr constructor performs two.
Where do the heap-allocations happen?
std::shared_ptr manages two entities:
the control block (stores meta data such as ref-counts, type-erased del...
Why should I use a pointer rather than the object itself?
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It's very unfortunate that you see dynamic allocation so often. That just shows how many bad C++ programmers there are.
In a sense, you have two questions bundled up into one. The first is when should we use dynamic allocation (using new)? The second is when should w...
Create singleton using GCD's dispatch_once in Objective-C
...ace MySingleton : NSObject
+(instancetype)sharedInstance;
+(instancetype)alloc __attribute__((unavailable("alloc not available, call sharedInstance instead")));
-(instancetype)init __attribute__((unavailable("init not available, call sharedInstance instead")));
+(instancetype)new __attribute__((un...
String length in bytes in JavaScript
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If you only need the length, it might be overkill to allocate a new string, do the actual conversion, take the length, and then discard the string. See my answer above for a function that just computes the length in an efficient manner.
– lovasoa
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Do threads have a distinct heap?
... a stack overflow.
Since all threads share the same heap, access to the allocator/deallocator must be synchronized. There are various methods and libraries for avoiding allocator contention.
Some languages allow you to create private pools of memory, or individual heaps, which you can assign ...
What is the difference between Google App Engine and Google Compute Engine?
...e docker to install s/w in GAE, does it mean google takes care of creating/allocating a linux instance with basic configurations and then runs docker on tops of it? In essence, compute engine adds additional responsibility of VM configs. Am I right?
– old-monk
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Segmentation fault on large array sizes
...The array is too big to fit in your program's stack address space.
If you allocate the array on the heap you should be fine, assuming your machine has enough memory.
int* array = new int[1000000];
But remember that this will require you to delete[] the array. A better solution would be to use st...
Difference between 'new operator' and 'operator new'?
...er, but it's a good question in any case.
Operator new is a function that allocates raw memory -- at least conceptually, it's not much different from malloc(). Though it's fairly unusual unless you're writing something like your own container, you can call operator new directly, like:
char *x = st...
Is there a max array length limit in C++?
...d char[].
Additionally, this upper limit may be influenced by the type of allocator used to construct the vector because an allocator is free to manage memory any way it wants. A very odd but nontheless conceivable allocator could pool memory in such a way that identical instances of an object shar...
Xcode without Storyboard and ARC
...gWithOptions: (NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
TestViewController *test = [[TestViewController alloc] initWithNibName:@"TestViewController" bundle...