[Bug fortran/29926] interface overloading assignment does not handle input types correctly

["jeffrey dot armstrong at analexcleveland dot com" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #2 from jeffrey dot armstrong at analexcleveland dot com  2006-11-21 18:11 -------
Obviously what I included is strictly a simplified example.  I'm trying to
emulate a 16-bit unsigned word in fortran, which should have a range from 0 to
65535.  There are proprietary reasons for doing so in our code.  To do this, i
am storing the bits in an integer(kind=2).  Note that I am strictly storing the
bits, not an integer value.  The easiest way to make an initial assignment is
to pass in an integer(kind=4) since it can handle the full range of unsigned
word values.  When passed into the assignment statement, the routine
uword_assign_4 strips the first 16 bits from the integer(kind=4) for storage
into the uword's integer(kind=2) storage.  Our module obviously has a
significant number of other unsigned word operations that are strictly
dependent on the bits stored in the integer(kind=2), not the actual integer
value.  

The example is meant to demonstrate that when I pass integer(kind=4) through
the assignment, the routine uword_assign_4 should be called, which accepts an
integer(kind=4) and performs the necessary bit assignment operations on the
integer(kind=2), but never directly assigns the integer(kind=4) value to an
integer(kind=2).  The compiler seems to be using uword_assign_2 when an
integer(kind=4) is used for assignment, which is erroneous.

I hope the above does clear up the example partially.  The example really is
meant to be trivial.  The code below compiles fine on Absoft Fortran versions 8
and 9 for Windows. 


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29926