C++ ptrmemfun break if FUNCTION_BOUNDARY < 2 * BITS_PER_UNIT

[Richard Earnshaw]

aoliva@redhat.com said:
> I don't want to extract a bit.  I want to extract the remaining bits.
> The delta was shifted left (or multiplied by 2) to make room for the
> vbit; now I want the delta back.  It's a signed offset.  

This is OK, provided that you can guarantee that the left shift won't 
cause the "sign" bit to change value.  That is

	((X << 1) MOD size) >> 1 == X

for all interesting values of X.

R.