std::unordered_map operator[] at element that didn't exist : is it garbage?

[grim prism]

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[wintry fern]

Unordered maps will 0 initialize new primative values from []

Basically you can imagine primatives having a default constructor that has garbage and an explicit default constructor that initializes to 0;

[tough rock]

Critical error:

You are sending requests too fast!

Requested by: rosepointer

[wintry fern]

Nooo I meant to copy that not delete :(

;compile

int x;
int y{};
printf("%d %d\n", x, y);

[tough rock]

Program Output

1651076199 0

rosepointer | 56ms | c++ | x86-64 gcc 14.1 | godbolt.org

[wintry fern]

There we go

[tough rock]

Program Output

1651076199 0

arni2671 | 56ms | c++ | x86-64 gcc 14.1 | godbolt.org

[grim prism]

Thank you and let us know if you have any more questions!

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[wintry fern]

Just final statements
In the docs for [] it mentions in regards to new values

this results in the key being copy constructed from key and the mapped value being value-initialized
Value-initialization refers to this
https://en.cppreference.com/w/cpp/language/value_initialization

Basically what I talked about. Primatives are set to 0, classes are default constructed. trivial classes are also set to all 0s