fix(bitfield): fix raw_mask
shifting twice
#262
Merged
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There's currently a bug in the
raw_mask
method onmycelium-bitfield
's packing spec types.raw_mask
returnsself.mask
shifted over by
self.shift
, with the intention of returning the actualmask used by the packing spec. But...the
self.mask
field is alreadyshifted to the correct bit position, so shifting it in the
raw_mask
method results in the mask being shifted over twice as many bits as it's
supposed to be.
This caused some very weird behavior in the
maitake
task statemanagement code, where attempting to toggle a bit using its
raw_mask
would accidentally clobber low bits of the ref count, resulting in a
ref-count underflow in some cases.