[Mono-list] Problem with while loop and Main returning void

[Leigh Dyer]

Hey guys,

I think I've found a minor bug in either mcs or the runtime. I was
writing a small app that has just has a Main() and a small while(true)
loop, with a break condition inside it. However, when I compiled my app
with mcs and ran it with mono, after breaking out of the while(true)
loop my program kept running - it seems to just keep re-running Main().
Running with mint exits at the end of the first run, but with a
"Trace/breakpoint trap" message.

However, if I change my Main() so that it returns int instead of void,
and add a "return 0;" to the end, everything works as expected.

I tried to isolate the problem with a small test case, and while it
doesn't exhibit exactly the same behaviour, it still doesn't work as
expected with Main() returning void - mint segfaults and mono returns
the following error:

** (process:18686): WARNING (recursed) **: unhandled exception
System.NullReferenceException: "A null value was found where an object
instance was required"

RESULT: -1

and then needs to be sent a ctrl-c.

I'm running the mono CVS debs from http://www.atoker.com/mono/ as of
yesterday on a Debian sid system.

I've attached both my small test case and the original app (it's very
small - all it does is iterate over the bytes of a text file looking for
non-ascii chars) - I hope they're of some use.

Thanks
Leigh

using System;

public class BreakTest
{
        public static void Main()
        //public static int Main()
        {
                while(true)
                {
                        Console.WriteLine("Breaking...");
                        break;
                }
                //return 0;
        }
}

using System;
using System.IO;

public class NonAscii
{
        public static void Main(string[] args)
        //public static int Main(string[] args)
        {
                FileStream s = new FileStream(args[0], FileMode.Open, FileAccess.Read);
                int line=0, ch=0;
                int x=0;
                
                while(true)
                {
                        int c = s.ReadByte();
                        Console.WriteLine("char " + x + ": " + c);
                        if(c == -1) break;

                        if(c == '\n')
                        {
                                line++; ch=0;
                        } else {
                                if(c > 127)
                                {
                                        Console.WriteLine("Non-ASCII char: line " + 
line + ", char " + ch);
                                }
                                ch++;
                        }
                        x++;
                }
                //return 0;
        }
}

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