Update git_array allocator to obey strict aliasing rules #6814
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Avoid sloppy aliasing in our (re-)allocation, which is undefined behavior. This has been problematic before and was helped by `volatile` (see b62a6a1) but that is not technically correct, and some compilers / architectures do not understand that `ptr` is changing due to its aliasing. Just make `git_array_alloc` behave like `realloc`, taking a `void *` and returning a `void *`.
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Avoid sloppy aliasing in our (re-)allocation, which is undefined behavior. This has been problematic before and was helped by
volatile(see b62a6a1) but that is not technically correct, and some compilers / architectures do not understand thatptris changing due to its aliasing.Just make
git_array_allocbehave likerealloc, taking avoid *and returning avoid *.