Bug 44751 - Incorrect code flow analysis with goto and out parameter causes CS0177
Summary: Incorrect code flow analysis with goto and out parameter causes CS0177
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: unspecified
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2016-09-26 18:56 UTC by Jonathan Chambers
Modified: 2016-09-29 20:42 UTC (History)
1 user (show)

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

Notice (2018-05-24): bugzilla.xamarin.com is now in read-only mode.

Please join us on Visual Studio Developer Community and in the Xamarin and Mono organizations on GitHub to continue tracking issues. Bugzilla will remain available for reference in read-only mode. We will continue to work on open Bugzilla bugs, copy them to the new locations as needed for follow-up, and add the new items under Related Links.

Our sincere thanks to everyone who has contributed on this bug tracker over the years. Thanks also for your understanding as we make these adjustments and improvements for the future.

Please create a new report on GitHub or Developer Community with your current version information, steps to reproduce, and relevant error messages or log files if you are hitting an issue that looks similar to this resolved bug and you do not yet see a matching new report.

Related Links:

Description Jonathan Chambers 2016-09-26 18:56:59 UTC
The following code fails to compile with Mono C# compiler while it compiles successfully with csc (or an older mono C# compiler).

GotoOutBug.cs(3,45): error CS0177: The out parameter `x' must be assigned to before control leaves the current method 
Compilation failed: 1 error(s), 0 warnings

public class GotoCodeFlowBug
	public static void Test(bool cond, out int x)
		if (cond)
			goto Label;
		x = 0;
Comment 1 Marek Safar 2016-09-29 20:42:14 UTC
Fixed in master and Mono 4.8