🚀 go-pugleaf

In article <MML.94Jan7135716@trinity.trinity.llnl.gov>, mml@trinity.trinity.llnl.gov ( Mitch M. Lee ) writes:
|> 
|> For some reason, when I compile the following with
|> gcc, it does not work. However when I compile with 
|> cc, it works as expected. Anyone know why? Perhaps
|> I'm not seeing something trivial here?
|> =================================================
|> #include <stdio.h>
|> #include <strings.h>  
|> #include <ctype.h>
|> 
|> char *stringtoupper(s)
|> char *s;
|> {
|> 
|>   while (*s != '\0') {
|>      *s = toupper(*s);
|>      s++;
|>   }
|> }
|> 
|> main()
|> { 
|>   printf("%s\n", stringtoupper("My test"));
|>   printf("%s\n", stringtoupper("works"));
|> }

You are trying to modify constant strings.  GCC won't let you do that unless
you compile with -fwriteable-strings; this forces gcc to put the strings into
the data segment, rather than a read-only segment and means that duplicated
strings can't be eliminated.

It's generally a bad idea to write code that depends on constant strings being
writeable in this way.