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0 pointspjmlp4y ago0 comments

With placement new you can allocate wherever you want, as the memory region is one of the parameters.

You can also overload it, so that it can be given as implicit parameter.

Modern C++ compilers are also able to do escape analysis and remove new altogether,

If you try AVR instead of X64, the optimization will be missing, which is only a side effect of the backend not having as much attention in what it looks into.

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londons_explore4y ago· 1 in thread

If you comment out the delete[] line, it returns the same output. Does that mean leaking memory is undefined behaviour?

pjmlpOP4y ago

Leaking memory is always undefined behaviour regardless of the language when talking about manual memory management.

What guarantees can you assure about the state of the application?

In any case, in this specific example for x64 it doesn't matter, because new gets optimized away.

However, if that optimization isn't done, e.g. AVR backend, then nasal daemons will be summoned.

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