Getting: "Compilation exited with code 134" when attempting to use "LLVM Optimizing Compiler" switch

4
votes

I'm getting a "Compilation exited with code 134" when attempting to use the "LLVM Optimizing Compiler" switch for release iPhone builds, using MonoTouch 4.0.1.

I don't get much information from build output window at all - just:

"Compilation exited with code 134, command:" MONO_PATH=(snip)/bin/iPhone/Release/LSiOS.app /Developer/MonoTouch/usr/bin/arm-darwin-mono --llvm --aot=mtriple=armv7-darwin,nimt-trampolines=2048,full,static,asmonly,nodebug,llvm-path=/Developer/MonoTouch/LLVM/bin/,outfile=/var/folders/03/033pAAGuHgGkIy4CorbVV++++TI/-Tmp-/tmp38107451.tmp/Newtonsoft.Json.MonoTouch.dll.7.s "(snip)/bin/iPhone/Release/LSiOS.app/Newtonsoft.Json.MonoTouch.dll" Mono Ahead of Time compiler - compiling assembly (snip)/mscorlib.dll

What is odd is that in earlier command lines, there is a correlation between the DLL mentioned in the arm-darwin-mono command line and what is the compiling, but in this case it says "mscorlib.dll".

Any thoughts?

3
monoxamarin.ioscompiler-errors
Hmmm - it definitely seems specific to Newtonsoft.Json.MonoTouch.dll being in the project. – scolestock

3 Answers

2
votes

I have found a few cases (googling and from bugzilla.xamarin.com) where the error code 134 is related to Mono.Linker being too aggressive (removing something that's needed).

This is easy to confirm by turning off the linker, i.e. "Don't link" in Linker Options. If the build works then you can try isolating the assembly where the linker makes a mistake.

E.g. add a "--linkskip=mscorlib" to the mtouch extra parameters and re-enable linking. This will link everything (Link All) or all SDK (Link SDK assemblies) except the assembly you selected (mscorlib in the example). That's only a workaround and a bug report should be filled so the issue can be fixed properly (and get you all the linker advantages).

However be warned that there are other issues sharing the same error code, like: http://ios.xamarin.com/Documentation/Troubleshoot#Error_134.3a_mtouch_failed_with_the_following_message.3a

YMMV

1
votes

mtouch does its native builds in parallel so the logs can be confusing, e.g. you can see a bit of assembly X output followed by some assembly Y output.

Reading the full log might help you (or us) to pinpoint the issue.

1
votes

I was having the exact same problem Scolestock. My app would build fine until I enabled llvm, then it was "Compilation exited with code 134, command" when trying to build the 7s for the app itself.

I'm elated to say that after 2 days of painstakingly whittling my app down to the core problem, I was able to isolate the issue to the usage of embedded dictionaries such as:

Dictionary<enum, Dictionary<enum, value>>

I was able to fix this by defining a class for the embedded dictionary and using that instead:

public class MyDefinition : Dictionary<enum, value>
{
}

...

public Dictionary<enum, MyDefinition>

Not sure if this will help you, but hopefully it'll help some poor soul who decides to use embedded dictionaries and runs into my same problem.