Well, I downloaded the file as well, extracted it into a folder in in the Pelle's C project folder and loaded the .ppj file and when executing a build, I get a series of warnings, including the one that the OP posted:
Building main.RES.
Building main.OBJ.
C:\Documents and Settings\Ralf\My Documents\Pelles C Projects\cwiz\main.c(247): warning #2229: Local 'c' is potentially used without being initialized.
C:\Documents and Settings\Ralf\My Documents\Pelles C Projects\cwiz\main.c(522): warning #2115: Local 'lenkwd' is initialized but never used.
C:\Documents and Settings\Ralf\My Documents\Pelles C Projects\cwiz\main.c(617): warning #2115: Local 'size' is initialized but never used.
C:\Documents and Settings\Ralf\My Documents\Pelles C Projects\cwiz\main.c(2053): warning #2234: Argument 3 to 'sprintf' does not match the format string; expected 'int' but found 'HWND'.
C:\Documents and Settings\Ralf\My Documents\Pelles C Projects\cwiz\main.c(2113): warning #2234: Argument 3 to 'sprintf' does not match the format string; expected 'int' but found 'HWND'.
Building cwiz.EXE.
Done.
At a first glance, the first warning is due to some really bad C programming, which indeed has the variable C uninitialized when called in this while loop
while(EOF!=c && pszBuf<bufferend){
(*pszBuf++)=c=(getc(pFile));
}
The second and third warnings are kind of ok, as they are just local variables defined to avoid a void typecasting of a function return.
However, the error message(s) that the OP posted does (at least at this time of the day for me) not make much sense, as it shows up on these lines of code
sprintf(text,"%d is the HWND of this window. For use as Parent Window for CreateWindowEx. cWiz.",hwndtest);
and
sprintf(text,"HWND of last created Window: %d: ",hwndex);
Looks like a strange parsing error to me where the text HWND somehow is evaluated by some macro, which should not happen...
Ralf