(j3.2006) Are functions in intrinsic modules "intrinsic"?
Mon Nov 16 22:52:26 EST 2015
This thread started internally because a user complained that we gave an
error for assumed-rank arguments to C_SIZEOF, pointing out that there was no
technical reason why this function should not allow C_SIZEOF.
That's "claiming" there was no technical reason. See below: there is one.
Should we reconsider and include C_SIZEOF in the list of places where
assumed-rank is allowed as an actual argument?
C_SIZEOF(array) is C_SIZEOF(array element) times the number of elements in
the array. If the assumed-rank dummy is associated with an assumed-size
array, this is not well-defined: well, the standard defines it, but existing
implementations with the traditional "just pass the address and forget about
the number of elements" would find it annoying to implement - not
impossible, but annoying, and with (possibly insignificant) increased
overhead for every routine that used assumed-size, not just the ones using
assumed-rank and C_SIZEOF.
Of course we could permit it with the additional requirement that the
argument not be associated with an assumed-size array, which C_SIZEOF
naturally excludes explicitly. I am not sure that that really is a good
idea though, as it is bound to fail at the most inconvenient time.
If the user actually wants the "sizeof" an element of an assumed-rank array,
this is available via
indeed that formulation also works for assumed-size arrays not just
More information about the J3