Storing constant string literals in a container

Question

I've got a struct foo bar of the form struct foo { const char* s, ... }; and a std::vector<foo> v; and I want to push_back a few foo's with constant values for the s member field, i.e.

bar.push_back({ "1", /*...*/ }); bar.push_back({ "2", /*...*/ }); bar.push_back({ "3", /*...*/ }); //...

Now, if I'm not totally wrong, this isn't safe, since the life time of the string literals are bounded to the scope of the initializer braces. So, the life time of the string literal "1" should have already been ended at the line of the second push_back.

How can we deal with this? Do we really need to create a second container strong std::string's and passing the corresponding c_str() pointers to bar?

"life time of the string literals are bounded" no, it is not. — n. m. could be an AI
– n. m. could be an AI, Commented Jun 4, 2021 at 10:28

lubgr · Accepted Answer · 2021-06-04 10:16:50Z

This is safe as long as you only ever initialize the const char *s with string literals . They have a lifetime that is identical to the lifetime of your program.

rep_movsd · Accepted Answer · 2021-06-04 10:25:04Z

The way to think of string literals is as if they were const pointers to const chars. In fact if you initialize two variables with the same string literal, they will actually point to the same address in most compiler implementations.

You can verify this by printing out the const char* pointers after casting them to integer.

Hence there is no question of "lifetime" of string literals anymore than the constant 99 has a lifetime.

They are literally literals

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