gnetlist needs much better error messages

[ahvezda]

gnetlist generates three error messages that do
not provide any clue as to how to find the source
of the problem.
 - "Missing Attributes (refdes and pin number)" (s_net.c)
 - "Could not find refdes on component and could not
find any special
attributes!"
    (s_traverse.c)
 - "Found a cpinlist head with a netname! [GND]
These error messages are in desparate need of a file
linenumber!

The third error appears to be normal, as it is
mentioned in the gsch2pcb tutorial, but in this case
was an error in the board file, since I don't have
any net named GND. It was some leftover GND:xx
nets in an old symbol create from a template.

In the first case, I eventually found that I had a
"dgnd" symbol that was missing a pinnumber. For the
benifit of anyone else encountering the same message,
this was found by looking at what was connected to
U?" in the netlist and looking on the schematic to
see what connected to what U? connected to.

Now, however I get large numbers of the second error.
 Looking at the netlist for U? shows that there is one
connection to U?-1 in VCC and one in U?-1 in DGND,
which gives no way to track these errors back to
their origin, though they look suspicously like
there is no problem in the source file at all and
it is improper handling in gnetlist.

I am not, and can not, use the power symbols supplied
with gschem and due to another gschem bug (update
component), if i tried to temporarily substitute
those symbols I would get a royal mess of duplicated
refdeses.

The only significant difference between my power
symbols and the gschem ones is that mine have a
pinlabel attribute which only one of the more
obscure gschem power symbols (gnd-2.sym) has.
Making a copy of the file with all the pinlabel
attributes stripped of the power symbols did not
seem to help.

There are exacly two references to U? in the
netlist, one connecting U?-1 to DGND and the other
connecting U?-1 to VCC. There are only 6 one pin
components (test points) and those are all accounted
for in the netlist.

here is my dgnd symbol, (typed in by hand since I
can't copy and paste between machines):

v20040111 1
P 200 200 200 150 1 0 0
{
T 70 140 5 5 0 1 0 0 1
pinnumber=1
T 260 130 5 5 0 0 0 1
pinlabel=DGND
T 120 140 5 5 0 1 0 0 1
pinseq=1
}
T 550 120 8 10 0 0 0 0 1
net=DGND:1
L 200 110 160 150 3 0 0 0 -1 -1
L 200 110 240 150 3 0 0 0 -1 -1
L 200 110 240 150 3 0 0 0 -1 -1

The problem can be reproduced by drawing a symbol
schematic with gschem's own
symbols:
   - R1 resistor-1 connected between vcc-1 and gnd-1
   - R2 resistor-1 connected between vcc-1 and gnd-1