Struct f { std::vector<type> ff;

Question

Struct f { std::vector<type> ff;

std::vector<type> fff;
} *fpn;

(f*)malloc(sizeof f)

is this wrong? ~latest msvc c++11 i have access violation _Pnext is 0xFFFFFFFFFFFFFFFF on push_back

0

12.07.2022

6 ответов

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Manav | avoid unnecessary messaging me

even if they try to construct the vector i think that'll lead to heap corruption.

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13.07.2022

Manav | avoid unnecessary messaging me

vectors do their own dynamic allocation, it's not good practice to use malloc on something where you don't fully control it's life time.

0

13.07.2022

Sergey

Manav | avoid unnecessary messaging me
even if they try to construct the vector i think t...

of course vectors will allocate their own stuff on heap. who knows how expected it is in this case. But this definitely will be another space and not one from the malloc in the code above. To call a vector constructor one can use in-place new

0

13.07.2022

Manav | avoid unnecessary messaging me

Sergey
of course vectors will allocate their own stuff on...

you mean placement new?

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13.07.2022

Manav | avoid unnecessary messaging me

can't think of any reason why you would dynamically allocate a struct with two vectors

0

13.07.2022