pub unsafe fn realloc(ptr: *mut u8, layout: Layout, new_size: usize) -> *mut u8
Reallocate memory with the global allocator.
This function forwards calls to the GlobalAlloc::realloc method of the allocator registered with the #[global_allocator] attribute if there is one, or the std crate’s default.
This function is expected to be deprecated in favor of the realloc method of the Global type when it and the AllocRef trait become stable.
See GlobalAlloc::realloc.
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Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
    https://doc.rust-lang.org/std/alloc/fn.realloc.html