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Update git_array allocator to obey strict aliasing rules#6814

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Merged

ethomson merged 1 commit intomainfromethomson/alloc

May 13, 2024

Merged

Update git_array allocator to obey strict aliasing rules#6814

ethomson merged 1 commit intomainfromethomson/alloc

May 13, 2024

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ethomson commentedMay 13, 2024

Avoid sloppy aliasing in our (re-)allocation, which is undefined behavior. This has been problematic before and was helped byvolatile (seeb62a6a1) but that is not technically correct, and some compilers / architectures do not understand thatptr is changing due to its aliasing.

Just makegit_array_alloc behave likerealloc, taking avoid * and returning avoid *.

array: treatgit_array ptrs asvoid *

54218b5

Avoid sloppy aliasing in our (re-)allocation, which is undefinedbehavior. This has been problematic before and was helped by `volatile`(seeb62a6a1) but that is nottechnically correct, and some compilers / architectures do notunderstand that `ptr` is changing due to its aliasing.Just make `git_array_alloc` behave like `realloc`, taking a `void *` andreturning a `void *`.