On Sun, Oct 01, 2017 at 04:45:13PM +0200, René Scharfe wrote: > lookup_blob() etc. can return NULL if the referenced object isn't of the > expected type. In theory it's wrong to reference the object member in > that case. In practice it's OK because it's located at offset 0 for all > types, so the pointer arithmetic (NULL + 0) is optimized out by the > compiler. The issue is reported by Clang's AddressSanitizer, though. > > Avoid the ASan error by casting the results of the lookup functions to > struct object pointers. That works fine with NULL pointers as well. We > already rely on the object member being first in all object types in > other places in the code.
Out of curiosity, did you have to do anything to coax this out of ASan (e.g., a specific version)? I've been running it pretty regularly and didn't see this one (I did switch from clang to gcc a month or two ago, but this code is pretty old, I think). -Peff
