Fix undefined behavior in operator[] #449
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meshula
approved these changes
Nov 1, 2024
cary-ilm
reviewed
Nov 1, 2024
If you take the address of a member, the pointer is only valid within the size of that member, such that accesses past that (i.e. to get to y or z of a vec3) are undefined behavior. by using this with a reinterpret cast, that tells the compiler the pointer space contains all values, and so avoids that. However, this may prevent other optimizations, so a larger change is recommended. Signed-off-by: Kimball Thurston <kdt3rd@gmail.com>
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If you take the address of a member, the pointer is only valid within the size of that member, such that accesses past that (i.e. to get to y or z of a vec3) are undefined behavior. by using this with a reinterpret cast, that tells the compiler the pointer space contains all values, and so avoids that. However, this may prevent other optimizations, so a larger change is recommended.
Addresses #446, thanks to @AlexMWells for the analysis