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Perhaps it could go at the end > of the chunk related definitions, closer to the other tag functions? ok. i'm happy to move it around. (i moved it down close to its first use). > > This refactoring also allows using mtag_enabled checks instead of > > USE_MTAG ifdefs when memory tagging support only changes code logic > > when memory tagging is enabled at runtime. > > Are you relying on the compiler to do the work of the old #ifdefs for > platforms without USE_MTAG set? I.e. are we sure that the compiled > binaries will have the mtag-related code optimized out? yes as described in my patch 6 response, i attempted to remove ifdefs. i think at -O1 we can rely on 'if (0) {...}' to be optimized out completely (but that code is still type checked and has to reference defined variables etc.) with -O0 i'd expect the code to be there in the compiled libc, just unreachable. i can add back the ifdefs if this seems too intrusive (it is now less clear that mtag related code does not affect the tagging disabled configuration). > > Otherwise LGTM with the above caveats. > > Reviewed-by: DJ Delorie