Can reassigning a C style string cause a memory leak?

Question

Can reassigning a C style string cause a memory leak? Like so:

char * s = "Hello!";
s = "Hello, world!";

My question may appear as stupid, but please bear with me; I am currently still a dummie in C++.

In the second line of code, the C style string s is longer, so does it have it internally reallocate memory? Does this cause a memory leak? And do I have to call delete?

Thanks

You're assigning pointers, not the actual values. And the actual values are literals generated by the compiler and hence are not heap allocated. — Hot Licks, Sep 22 '13 at 14:17
(It's really important to understand the difference between `some_data` and a pointer to `some_data`.) — Hot Licks, Sep 22 '13 at 14:19
It should actually be `const char *s = ...`, because string literals are pointers to non-modifiable (constant) memory — leemes, Sep 22 '13 at 14:39
@6502: Ok. I guess I learnt somethin then:) I don't if I will use it. It is with char array it is not. — user2672165, Sep 22 '13 at 16:21

score 4 · Accepted Answer · edited May 23 '17 at 10:31

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Actually, technically no. String literals are provided special static allocation. See

Is a string literal in c++ created in static memory?

edited May 23 '17 at 10:31

Community

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answered Sep 22 '13 at 14:17

rileyberton

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score 3 · Answer 2 · edited Jun 20 '20 at 09:12

Memory leak are caused by dynamic memory allocation.

There is no dynamic allocation here, so no memory leak.

Actually, string literals have static storage duration. The standard says (draft n3690):

3.7.1 Static storage duration [basic.stc.static]

All variables which do not have dynamic storage duration, do not have thread storage duration, and are not local have static storage duration. The storage for these entities shall last for the duration of the program.

score 1 · Answer 3 · answered Sep 22 '13 at 14:15

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There is no dynamic memory allocation so there is no leak. What you have is a pointer pointing to a string literal which is stored somewhere in implementation defined read only memory.

answered Sep 22 '13 at 14:15

Alok Save

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Can reassigning a C style string cause a memory leak?

3 Answers3