Avoid invalid gcc 14.3 warning about array bounds in mbedtls_xor #73
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tomi-font
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Could you rather first make a PR in upstream Mbed TLS and then cherry pick it here?
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Thanks! If you want to get this merged here before it's merged upstream then please add a reference to the upstream PR (e.g. PR #) in the commit message. Otherwise we can just wait and cherry pick the upstream commit (with |
It's blocking SDK version 0.18, so we should probably not wait (the fix is pretty easy to review in isolation). |
tomi-font
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Maybe align this with Mbed-TLS/mbedtls#10318 and then we can merge this PR?
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now missing the upstream PR # in the commit message 🙃
The combination of the multi-byte loop with the single byte loop confuses GCC 14.3's array bounds checker. When the loop size is constant, check to see if it is a multiple of the multi-byte size and bail early. As this will be evaluated at compile time, there should be no run-time cost. This change uses the __builtin_constant_p compile-time operation. To check if that is supported, the change uses the existing MBEDTLS_HAS_BUILTIN macro. That macro was defined later in library/common.h than is needed for this change, so it was moved up to join some other macros that looked similar. Upstream PR: Mbed-TLS/mbedtls#10318 Signed-off-by: Keith Packard <keithp@keithp.com>
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The combination of the multi-byte loop with the single byte loop confuses GCC 14.3's array bounds checker. When the loop size is constant, check to see if it is a multiple of the multi-byte size and bail early. As this will be evaluated at compile time, there should be no run-time cost.