Bug 38992 - error CS1009: Unrecognized escape sequence '\_' in $@ String
Summary: error CS1009: Unrecognized escape sequence '\_' in $@ String
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: 4.0.0
Hardware: PC Linux
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2016-02-22 15:54 UTC by jeffp1618
Modified: 2016-02-23 21:52 UTC (History)
1 user (show)

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

Simple example of compilation failure (171 bytes, text/plain)
2016-02-22 15:54 UTC, jeffp1618

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Description jeffp1618 2016-02-22 15:54:17 UTC
Created attachment 15126 [details]
Simple example of compilation failure

When compiling the following simple code (also attached as BugReport.cs)

using System;
class BugReport
	public static void Main(string[] args)
		var timespan = new TimeSpan();

with mcs BugReport.cs it reports the following error message:

error CS1009: Unrecognized escape sequence '\_'

If I try and run this on Microsoft .NET it compiles successfully and when the exe is run it outputs:
Comment 1 jeffp1618 2016-02-22 15:55:50 UTC
Compiler version:
Mono C# compiler version
Comment 2 Marek Safar 2016-02-23 21:52:49 UTC
Fixed in master and mono 4.4