Fix crash in nk_buffer_realloc and forbid the use of realloc #878
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In short: the default implementation of nk_allocator (aka nk_malloc) is fundamentally broken, and should have used realloc instead of malloc. This led to the strange workaround in nk_buffer_realloc that would crash whenever you use custom allocator with correct realloc assumption. We cannot change nk_malloc at this point, as people could have implemented their own allocators based on it, but we can ensure that Nuklear itself will never try to reallocate memory. Fixes: Immediate-Mode-UI#768
sleeptightAnsiC
commented
Jan 27, 2026
sleeptightAnsiC
commented
Jan 27, 2026
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Please read the linked issue for exhaustive explanation of this change.
In short: the default implementation of nk_allocator (aka nk_malloc) is fundamentally broken, and should have used realloc instead of malloc in the first place. This led to the strange workaround in nk_buffer_realloc that would crash whenever you use custom allocator with correct realloc assumption. We cannot change nk_malloc at this point, as people could have implemented their own allocators based on it, but we can ensure that Nuklear itself will never try to reallocate memory.
Yes, this is ugly, but it will not break any existing code, neither in nuklear nor in any other library/app based on it, and we can always change it to something else later (but I don't believe there is any better solution)
Fixes: #768