Hi Florian, On Wed, 2021-12-15 at 23:40 +0100, Florian Weimer via Elfutils-devel wrote: > * Mark Wielaard: > > > This seems a wrong warning since we aren't accessing the field member > > of the struct, but are taking the address of it. But we can do the > > same by adding the field offsetof to the base address. Which doesn't > > trigger a runtime error. > > I think the warning is correct. I believe it is motivated by the GCC > optimizers using this to infer alignment of the original pointer. It > won't make a difference for this expression, but it can cause crashes > elsewhere with strict-alignment targets.
I think that does make sense. I tweaked to commit message a bit before pushing the commit to say: We aren't actually accessing the field member of the struct, but are taking the address of it. Which the compiler can take as a hint that the address is correctly aligned. But we can do the same by adding the field offsetof to the base address. Which doesn't trigger a runtime error. Thanks, Mark
