Build fails without /p:TargetFrameworkVersion="v4.5" on Ubuntu 16.04 LTS

[Lukas-Dresel]

I setup a new virtual machine running Ubuntu 16.04 LTS and installed mono-xbuild, mono-complete and mono-devel.

I attempt building from the src/ subdirectory by calling xbuild Reko-decompiler.sln

This gives me a whole slew of errors, which i can provide if necessary, but most notably the following ones:

CSC: error CS0518: The predefined type 'System.Object' is not defined or imported This continues with System.ValueType, System.Attribute and others

When building with /p:TargetFrameworkVersion="v4.5" the build completes.

[Lukas-Dresel]

This should at least be mentioned somewhere on the README, or am i doing something wrong?

[uxmal]

Thanks for reporting this; can you provide a full dump of the errors in a zipped up file, so I can analyze? My Ubuntu environment doesn't exhibit this error, so I'd like to understand what differs.

[uxmal]

I just pushed 2136ff2 that ensures that all csproj files are referring to .NET version 4.0. It might make a difference. I suggest you try rebuilding with that commit and see if it helps.

[Lukas-Dresel]

Unfortunately for some reason github doesn't like me uploading stuff, i don't know why.

Instead the output of my build can be found here: http://pastebin.com/Wp5EgFFu

I'll check if it builds now.

[Lukas-Dresel]

The same problem occurs, but less often. New output here: http://pastebin.com/956VB6Lp This might however be a result of already compiled stuff, haven't figured out how to make a clean from the commandline yet

[uxmal]

Appreciate your effort. It's National Day over here so I may not be able to analyze this until tonight.

[uxmal]

Have you considered updating your toolchain? The Travis-CI logs (https://travis-ci.org/uxmal/reko) report no errors when running with the following

XBuild Engine Version 12.0
Mono, Version 4.2.3.0

The errors you are seeing are extreme; obviously System.Object must exist in any CLR implementation. My first guess is that you have garbage from a previous build. To build clean, use xbuild /target:clean (yes, use slash, xbuild copies its behavior from msbuild)

[Lukas-Dresel]

Okay, so i just tested a clean and remake, the error still persists. I'm out of ideas what it could be by now...

I could try updating the toolchain, but would have to do so manually since sudo apt upgrade mono-devel mono-complete mono-xbuild reports all three as up to date. (specifically version 4.2.1.102+dfsg2-7ubuntu4)

Maybe i can switch to experimental ubuntu apt repos to fix this

[Lukas-Dresel]

But for now i'm out of ideas what else it could be, specifically because it works with forcing the target .net framework to version 4.5 from the commandline.

[uxmal]

It's odd because there are no longer -- to my knowledge -- any dependencies on fwk 4.5 in the codebase. However, it could be that the affected projects (I'm thinking Decompiler.csproj) has some other settings in it that is causing xbuild / mono to lose it.

Unfortunately, I'm unable to reproduce this on my own Ubuntu VM, nor during the Travis CI builds. I'm going to look at Decompiler.csproj and see if there is anything that might be the cause.

[Lukas-Dresel]

What toolchain version are u using in your VM? Installed from package manager or built or pre-built?

[uxmal]

It's been such a long time since I built the VMm but I definitlely grabbed the mono pieces from go-mono, not the default Ubuntu repo. I'm a Linux n00b so I didn't try building myself. (let's move onto https://gitter.im/uxmal/reko if you're able, to avoid spamming)

[uxmal]

I'm resolving this as "workaround exists", namely the one you mentioned in the title of this issue. Adding the following link, describing why there are missing CLR assemblies on RedHat: https://bugzilla.redhat.com/show_bug.cgi?id=1255204 and where to grab missing CLR assemblies: git://github.com/mono/reference-assemblies.git