Should this go [OT]??

From Bob A:
> So, try this:

>  ( (union_lo_hi *) &eth_length)->b.l = 123;  // assign low byte
           ^
           took this out

This doesn't compile either - same error messages.  Is this a CCS
problem?

From John D (a while ago - sorry):

> My_16bitInt = *(WORD *)&bytearray[5];

This does compile, although with the CCS compiler it is not quite as
efficient.  To address your other comments, I am always checking to
see what the compiler is producing - that's how I got involved in this
thread!

This seems to be getting quite complex for the original problem.  To
recap, this part of this thread is discussing a c standard way of
addressing the low and high bytes of a word variable, to force more
efficient compiling for situations like assigning consecutive array
bytes to a word:
     word_var = byte_array[2] + byte_array[3] * 256;

CCS compiles this in 7 instructions with the 18 instruction set - it
should be able to do this in 2 - so we really are quibbling about small
amounts of code here - but for me, has raised all sorts of interesting
c possibiities.  John's suggestion above compiles in 9 instructions,
while I haven't been able to get the advanced structure/union stuff to
compile at all.  I've always used CCS's '#byte' directive, which is
non-standard c.  I thought I would look for something simpler, but I
still have questions, if anyone is still hanging with me.
It seems just a structure would give the desired access:

     struct lo_hi {char lo; char hi;};
     struct lo_hi word_var;

     word_var.lo = byte_array[2];
     word_var.hi = byte_array[3];

This compiles in the desired 2 instructions; however, when I want to
just use the full variable,

this works:        word_var = 1000;
but this doesn't:  if (word_var2 > word_var)

for the compare, CCS insists on a structure element; I want it treated
as a single 16 bit variable.
Is this how how these *should* be treated??

Thanks again for any suggestions.

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