Don't pass null to memcpy and simplify debug assert - #2253
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Skip empty copies in ByteString::SetSmall so default-constructed string views do not trigger nonnull-attribute diagnostics from libc memcpy declarations. Checking at the copy also covers borrowed and external string construction. Add a regression test using the existing heap and arena allocator cases. C2y permits zero-length operations on null pointers, but existing libc headers can still annotate memcpy arguments as unconditionally nonnull. Signed-off-by: Anuraag Agrawal <anuraaga@gmail.com>
Use the non-empty precondition directly instead of comparing size_t with an int literal through Abseil's templated comparison helper. This avoids -Wsign-compare in debug builds without narrowing the qualifier count. Signed-off-by: Anuraag Agrawal <anuraaga@gmail.com>
anuraaga
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Sep 8, 2026
| const google::protobuf::DescriptorPool* absl_nonnull descriptor_pool, | ||
| google::protobuf::MessageFactory* absl_nonnull message_factory, | ||
| google::protobuf::Arena* absl_nonnull arena) const { | ||
| ABSL_DCHECK_GT(qualifiers.size(), 0); |
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Compares unsigned long to int triggering signedness warning. Trivial to just switch to a boolean check
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Envoy has had some very long-standing patches for cel-cpp that get triggered by its stricter build that enables address sanitization and
-Wextra. AFAICT these small issues are all that prevents Envoy from updating to a latest upstream cel-cpp dependency (the other parts of the patch are already present here).https://github.com/envoyproxy/bazel-registry/blob/b6e15c00b1c0493cd194b1b248c562bd8bc46648/modules/cel-cpp/0.14.0.envoy/patches/cel-cpp.patch
A
memcpyalways needs to have non-null pointers, at least until C20 becomes mainstream, which is typically accomplished by a length check. While downstream effects are unlikely, it seems theoretically possible for SetSmall to be inlined before a nullptr check that gets erased, so a highly theoretical bug that triggers sanitizers.Envoy being able to update would unblock work to support Windows @yanavlasov is working on. I suspect being able to use upstream cel-cpp would make @phlax happy too