Devirtualize destructors #37708
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Devirtualize destructors #37708
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According to the C++ Core Guideline C.35 [1], "A base class destructor should be either public and virtual, or protected and non-virtual". Matter has a ton of virtual interfaces but objects are very rarely destroyed polymorphically. Hence, the virtual d-tors play no role but bloating the firmware. Turn some virtual d-tors into non-virtual protected. [1] https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#Rc-dtor-virtual
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This one NEEDS to remain virtual as it is widely deployed by ecosystems with non-default operations.
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Do you mean that ecosystems destroy this object using the base pointer?
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According to the C++ Core Guideline C.35 [1], "A base class destructor should be either public and virtual, or protected and non-virtual".
Matter has a ton of virtual interfaces but objects are very rarely destroyed polymorphically. Hence, the virtual d-tors play no role but bloating the firmware.
Turn some virtual d-tors into non-virtual protected.
[1] https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#Rc-dtor-virtual
Testing
This is work in progress. I created this PR to see the reception of this proposal and assess the gain.
So far, I see over 0.5kB flash reduction on nRF lock-app by changing just a few d-tors, so I think it can give us a few K and the effort is pretty mechanical.