SQL0312 Variable not defined or not usable error

I think I have found a bug in the SQL precompiler at V7R1. I have a DS defined that SQL fetches into, as well as the "SDS" data structure immediately follows it, followed by a line with a "D" in column six and nothing else (see below).

dcl-ds dsfetch qualified;
message like(zzqrymsg);
run_time like(zzruntim);
flag like(zzflag);
type like(zztyp);
recid like(zzid);
level like(zzlevel);
qrynum like(zznum);
qrymsg like(zzmsg);
qrycom like(zzcom);
end-ds;

D SDS
D Program 1 10
D User 254 263
D

I noticed that the fields in the SDS data structure were not used, so I commented out those 3 lines. Then, when I recompiled, I got the SQL0312 error. Turns out that the DS was fine. What I found was that the one "D" line with nothing else in it was causing the error. As soon as I placed an asterisk in column 6 of that line, the compile was fine (see below).

D****** SDS
D****** Program 1 10
D****** User 254 263
D******

So, the precompiler does not like D specs without any specs, when it follows the fetched DS definition. However, if you put an asterisk in column 6 it is fine, and if I had left the SDS DS intact, it is also fine.

Hope this helps someone who is stuck with this error.