CS1576 after upgrade to 14.04.1

[lordbah2]

Upgraded from 13.10 to 14.04.1 and my web site stopped working. What changed with mod-mono, mono, apache, etc. between 13.10 and 14.04.1?

Error CS1576. I don't use the #line directive at all. Something during on-demand compilation of an ASP.NET page?

Application Exception

System.Web.Compilation.CompilationException

CS1576: The line number specified for #line directive is missing or invalid

Description: Error compiling a resource required to service this request. Review your source file and modify it to fix this error.
Details: CS1576: The line number specified for #line directive is missing or invalid
Error origin: Compiler
Error source file: /Standings.aspx
Exception stack trace:
at System.Web.Compilation.AssemblyBuilder.BuildAssemb ly (System.Web.VirtualPath virtualPath, System.CodeDom.Compiler.CompilerParameters options) [0x00000] in <filename unknown>:0 at System.Web.Compilation.AssemblyBuilder.BuildAssemb ly (System.Web.VirtualPath virtualPath) [0x00000] in <filename unknown>:0 at System.Web.Compilation.BuildManager.GenerateAssemb ly (System.Web.Compilation.AssemblyBuilder abuilder, System.Web.Compilation.BuildProviderGroup group, System.Web.VirtualPath vp, Boolean debug) [0x00000] in <filename unknown>:0 at System.Web.Compilation.BuildManager.BuildInner (System.Web.VirtualPath vp, Boolean debug) [0x00000] in <filename unknown>:0
Version Information: 3.2.8 (Debian 3.2.8+dfsg-4ubuntu1); ASP.NET Version: 4.0.30319.17020

[lordbah2]

Well, that's weird. The first line of the .aspx file is

<%@ Page Language="C#" MasterPageFile="~/UserPageTemplate.master" %>

and I get the error. If I add Trace="true" then I do not get the error and the page works (not counting the gobs of trace info in it).

[lordbah2]

And weirder. I added the Xamarin repository and upgraded mono from 3.2.8 to 3.6.0 and restarted apache2. One page which previously had that failure now works. Other pages still fail the same way.

Edit: actually, that one success is not repeatable. I have no idea what's going on ...

[lordbah2]

Maybe I should downgrade mono back to the version it was in Ubuntu 13.10. Is there a way to get synaptic to use https://launchpad.net/ubuntu/trusty/amd64/mono-complete/2.10.8.1-5ubuntu2?