stack overflow in F# compiler running under mono

Question

I'm updating the tooling for my project llvm-fs , so I installed the new version of mono and tried to compile it. Using either mono 3.10.0 with fsharpc 3.1 under OS X or mono 3.2.8 with fsharpc 3.0 under ubuntu the compile fails with a stack overflow:

Unhandled Exception:
System.StackOverflowException: The requested operation caused a stack overflow.
  at (wrapper managed-to-native) object:__icall_wrapper_mono_object_isinst (object,intptr)
  at (wrapper castclass) object:__castclass_with_cache (object,intptr,intptr)
  at Microsoft.FSharp.Compiler.Driver+DelayedDisposables.System-IDisposable-Dispose () [0x00000] in <filename unknown>:0 
  at Microsoft.FSharp.Compiler.Driver.typecheckAndCompile (System.String[] argv, Boolean bannerAlreadyPrinted, Exiter exiter, Microsoft.FSharp.Compiler.ErrorLoggerProvider errorLoggerProvider) [0x00000] in <filename unknown>:0 
  at Microsoft.FSharp.Compiler.Driver.mainCompile (System.String[] argv, Boolean bannerAlreadyPrinted, Exiter exiter) [0x00000] in <filename unknown>:0 
  at Microsoft.FSharp.Compiler.CommandLineMain.runMain (System.String[] argv) [0x00000] in <filename unknown>:0 
  at Microsoft.FSharp.Compiler.CommandLineMain.main (System.String[] argv) [0x00000] in <filename unknown>:0 
[ERROR] FATAL UNHANDLED EXCEPTION: System.StackOverflowException: The requested operation caused a stack overflow.
  at (wrapper managed-to-native) object:__icall_wrapper_mono_object_isinst (object,intptr)
  at (wrapper castclass) object:__castclass_with_cache (object,intptr,intptr)
  at Microsoft.FSharp.Compiler.Driver+DelayedDisposables.System-IDisposable-Dispose () [0x00000] in <filename unknown>:0 
  at Microsoft.FSharp.Compiler.Driver.typecheckAndCompile (System.String[] argv, Boolean bannerAlreadyPrinted, Exiter exiter, Microsoft.FSharp.Compiler.ErrorLoggerProvider errorLoggerProvider) [0x00000] in <filename unknown>:0 
  at Microsoft.FSharp.Compiler.Driver.mainCompile (System.String[] argv, Boolean bannerAlreadyPrinted, Exiter exiter) [0x00000] in <filename unknown>:0 
  at Microsoft.FSharp.Compiler.CommandLineMain.runMain (System.String[] argv) [0x00000] in <filename unknown>:0 
  at Microsoft.FSharp.Compiler.CommandLineMain.main (System.String[] argv) [0x00000] in <filename unknown>:0 

You can reproduce this error on linux or OS X by doing the following:

git clone git@github.com:fsprojects/llvm-fs.git
cd llvm-fs/
FSC=fsharpc ./build.bash

Under windows fsc 12.0.30815.0 the compile completes with no errors:

fsc --nologo --debug --sig:LLVMFSharp.fsi --target:library --out:LLVMFSharp.dll src/LLVM/FFIUtil.fs src/LLVM/Generated.fs src/LLVM/Core.fs src/LLVM/BitReader.fs src/LLVM/ExecutionEngine.fs src/LLVM/Extra.fs src/LLVM/Target.fs src/LLVM/Quote.fs

Is this a known issue and is there any way to work around it? I've tried passing different options to the mono runtime and none resulted in the compiler exiting normally. I do remember in the past mono has had some problems respecting tailcall instructions but I thought that those problems were mostly resolved. Thanks!

Answer 1

This is too long for a comment, but the error is triggered by this bit of code from generated.fs (in that commenting it out stops the stack overflow - there is an error later once this is commented out) (from line 6496-6506):

 [<DllImport(
            llvmAssemblyName,
            EntryPoint="LLVMRunFunction",
            CallingConvention=CallingConvention.Cdecl,
            CharSet=CharSet.Ansi)>]
        extern void* (* LLVMGenericValueRef *) runFunctionNative(
            void* (* LLVMExecutionEngineRef *) EE,
            void* (* LLVMValueRef *) F,
            uint32 NumArgs,
            void* (* LLVMGenericValueRef* *) Args)
        // I don't know how to generate an "F# friendly" version of LLVMRunFunction

The crash is occuring in the code that outputs the signature file.

Disabling the signature file fixes the problem (but there is still an underlying bug somewhere).