Bug 17310 - stepping through code breaks execution
Summary: stepping through code breaks execution
Status: RESOLVED FIXED
Alias: None
Product: Runtime
Classification: Mono
Component: Debugger ()
Version: unspecified
Hardware: PC Linux
: --- normal
Target Milestone: ---
Assignee: Zoltan Varga
URL:
Depends on:
Blocks:
 
Reported: 2014-01-18 12:12 UTC by Sander
Modified: 2014-01-21 18:58 UTC (History)
4 users (show)

Tags:
Is this bug a regression?: ---
Last known good build:

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Status:
RESOLVED FIXED

Description Sander 2014-01-18 12:12:07 UTC
In the following code: 

static double f(double a)
{
	return a * 2;
}
public static void Main (string[] args)
{
	double d = 2;
	double d2 = f (d);
	Console.WriteLine ("f(" + d + ") = " + d2);
	Console.ReadLine ();
}

the output is incorrect when stepping through code. If I place a breakpoint in the first line of Main, and then Step Over until I reach the readline, the output is incorrect in both the console and the locals view (it reads 3.75). If I place a breakpoint on each line, and repeat Run to the readline (rather than stepping), the output is correct. 

If I step into the f() function, I see the parameter A equals 4.5 in the locals view, and the function returns 1.5.
Comment 1 Zoltan Varga 2014-01-18 22:12:17 UTC
What platform/mono version is this ?
Comment 2 Sander 2014-01-19 04:46:27 UTC
I use MonoDevelop 4.1.7 on Ubuntu Linux.
mono --version yields:
Mono Runtime Engine version 3.2.3 (master/9acd6e3 vr okt 18 22:00:18 CEST 2013)
Copyright (C) 2002-2013 Novell, Inc, Xamarin Inc and Contributors. www.mono-project.com
	TLS:           __thread
	SIGSEGV:       altstack
	Notifications: epoll
	Architecture:  amd64
	Disabled:      none
	Misc:          softdebug 
	LLVM:          supported, not enabled.
	GC:            sgen
Comment 3 Zoltan Varga 2014-01-21 14:51:03 UTC
I can reproduce this. Seems like its amd64 only, the x86 version works fine.
Comment 4 Zoltan Varga 2014-01-21 18:58:57 UTC
Fixed in master 216ccda87a16eb92fd89ef54e0d9e8af5fa8f6b3.