warning message in gcc 3.3, but not gcc 2.95

warning message in gcc 3.3, but not gcc 2.95

[Raymond Cheng]

To All: 

I recently installed gcc 3.3 onto my laptop while desktop still has the 
old gcc 2.95. And then I tried "testing" the compiler with one of my old 
code. The new gcc gives

  warning: deprecated use of label at end of compound statement 

while the old gcc gives no warning. The program still runs (that is 
compiled by the new gcc). Is the new gcc catching something important? 

Btw, what this warning message means. I already looked at the docs in 
gcc.gnu.org and did a search on this mailing list. Can someone tells me
what this warning means or point me to a docs that has a list of warning 
messages (not a just a tutorial to gcc)? 

Thanks! 

Sheng-Chieh 

Re: warning message in gcc 3.3, but not gcc 2.95

[llewelly]

Raymond Cheng <rscheng@computermail.net> writes:

> To All: 
> 
> I recently installed gcc 3.3 onto my laptop while desktop still has the 
> old gcc 2.95. And then I tried "testing" the compiler with one of my old 
> code. The new gcc gives
> 
>   warning: deprecated use of label at end of compound statement
[snip]

'depercated' in a warning is issued for a gcc extension which will be
    removed in some future rlease. For example, with gcc 3.4.0, this
    code:

    int main()
      {
        foo:
      }

    results in this error message:

    label_at_compound_statement_end.c: In function 'main':
    label_at_compound_statement_end.c:5: error: label at end of compound
      statement

If you place a semi-colon after the label warning (error with 3.4)
    vanishes. ISO C requires a semi-colon after the label.