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sizeof continues to return 4 instead of actual size


sizeof continues to return 4 instead of actual size

By : ShankJ
Date : November 20 2020, 07:00 PM
I think the issue was by ths following , sizeof returns the size of an expression. For you, that's a std::string and for your implementation of std::string, that's four. (Probably a pointer to the buffer, internally.)
But you see, that buffer is only pointed to by the string, it has no effect on the size of the std::string itself. You want message.size() for that, which gives you the size of the string being pointed to by that buffer pointer.
code :


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Does sizeof return the size of a malloc memory allocation?

Does sizeof return the size of a malloc memory allocation?


By : Philip Bley
Date : March 29 2020, 07:55 AM
I hope this helps . What is the problem with the following memory allocation?
code :
sizeof(buffer) 
sizeof std::aligned_storage the actual available storage size?

sizeof std::aligned_storage the actual available storage size?


By : Mel Dawnfield
Date : March 29 2020, 07:55 AM
wish of those help std::aligned_storage::type is a POD type. This means it is plain old data.
How it came to be does not matter. It is merely plain old data.
Assert sizeof(obj) at compile time and print the actual size if it doesn't match (c++98)

Assert sizeof(obj) at compile time and print the actual size if it doesn't match (c++98)


By : user2754751
Date : March 29 2020, 07:55 AM
this will help I have a structure obj and a function (in separate file) that populates this structure with some values. Due to the system design this function couldn't be a part of the structure (which is generated by a script). Eventually the structure may change, so the function should be updated accordingly. The problem is that the developer that changes the structure might forget to update the corresponding function, and the compiler wouldn't remind about that (if some parameters will be added, and existing parameters remain the same). , One way to "display" value at compile time is in the error:
code :
template <std::size_t N> struct Debug; // No definition

template <> struct Debug<1234> {}; // Definition for "old" sizeof;

template struct Debug<sizeof(obj)>; // Issue error if definition is missing
Does sizeof() in c# return only a size of type itself or it counts the reference size as well

Does sizeof() in c# return only a size of type itself or it counts the reference size as well


By : kirubasi
Date : March 29 2020, 07:55 AM
fixed the issue. Will look into that further If I do , Everything in your question is wrong.
Given a certain fixed platform, can sizeof return different size for the same type?

Given a certain fixed platform, can sizeof return different size for the same type?


By : Alex D
Date : March 29 2020, 07:55 AM
I wish did fix the issue. Quotes from Microsoft's Data Type Ranges:
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