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Querying the alignment of a type

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The alignment requirement of a type can be queried using the alignof keyword as a unary operator. The result is a constant expression of type std::size_t, i.e., it can be evaluated at compile time. 

#include <iostream>
int main() {
    std::cout << "The alignment requirement of int is: " << alignof(int) << '\n';
}

Possible output

The alignment requirement of int is: 4

If applied to an array, it yields the alignment requirement of the element type. If applied to a reference type, it yields the alignment requirement of the referenced type. (References themselves have no alignment, since they are not objects.)

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Table Of Contents
0 Getting started
1 Literals
2 Basic type keywords
3 Operator precedence
4 Floating point arithmetic
5 Bit operators
6 Bit manipulation
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8 Arrays
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11 Loops
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92 Trailing return type
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102 Attributes
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125 Alignment
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128 Curiusly recurring template pattern
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130 Typedef and type aliases
131 Layout of object types
132 C incompatibilities
133 Optimization
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135 Thread synchronization
136 Debugging
137 Futures and promises
138 More undefined behaviors
139 Mutexes
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141 Unit testing
142 decltype
143 Digit separators
144 C++ Containers
145 Arithmetic meta-programming
146 Contributors