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From: "bmcfadden at cdp dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/31977]  New: can return OK from "int main()" without a return statement by using a goto before the return
Date: Thu, 17 May 2007 15:46:00 -0000	[thread overview]
Message-ID: <bug-31977-14564@http.gcc.gnu.org/bugzilla/> (raw)

I'm using gcc 3.4.5, and I was looking into a weird condition.  The following
program compiles OK:

#include <stdio.h>
int alloc()
{
return 0;
}
int main(int argc, char* argv[])
{
       printf("Testing!\n");
       if(alloc() == 0)goto Radhe;
       return 0;
Radhe:
         printf("Hello\n");
}

The result is a program which prints "Testing", then "Hello", and then exits. 
I and a few other people expect that the compiler would generate an error
during compile, because main should return an int, and not all code paths have
a return statement; however, both gcc and msvc are compiling this OK.

added note: this bug was recently discussed on the NTDEV mailing list.


-- 
           Summary: can return OK from "int main()" without a return
                    statement by using a goto before the return
           Product: gcc
           Version: 3.4.5
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: bmcfadden at cdp dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31977


             reply	other threads:[~2007-05-17 15:46 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-05-17 15:46 bmcfadden at cdp dot com [this message]
2007-05-17 15:48 ` [Bug c/31977] " bmcfadden at cdp dot com
2007-05-17 15:52 ` bmcfadden at cdp dot com
2007-05-17 15:54 ` bmcfadden at cdp dot com
2007-05-17 17:53 ` pinskia at gcc dot gnu dot org
2007-05-17 19:39 ` bangerth at dealii dot org
2007-05-17 19:45 ` pinskia at gcc dot gnu dot org

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