Generated executables have missing execute bit

[0xmohit]

$  uname -a
Linux earth 4.2.0-34-generic #39-Ubuntu SMP Thu Mar 10 22:13:01 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

F# obtained as per instructions on http://fsharp.org/use/linux/.

Test file:

$  cat a.fs 
printfn "Hey"

Now compile:

$  fsharpc --nologo a.fs 

Check the result:

$  ls -l
total 8
-rw-rw-r-- 1 mohit mohit 3584 Mar 25 20:27 a.exe
-rw-rw-r-- 1 mohit mohit   14 Mar 25 20:07 a.fs

The executable a.exe doesn't have the execute bit set.

In case it matters, here's the umask:

$  umask 
0002

The compiler version from fsharpc --help reads F# Compiler for F# 4.0 (Open Source Edition)

[smoothdeveloper]

@0xmohit I think you anyways need to execute the program like this:

mono a.exe so I don't think it really matters.

What is the behaviour of C# compiler?

[0xmohit]

Executables generated by mcs don't exhibit this behavior, i.e. mcs foo.cs generates foo.exe which has the execute bit(s) set.

[0xmohit]

It is worthwhile adding that this issue (with fsharpc) wasn't observed earlier -- seems that the change is due to a recent package update.

[dsyme]

The code to set the executable permissions is here: https://github.com/fsharp/fsharp/blob/master/src/absil/ilwrite.fs#L3414

It might be that this code is now failing for some reason on recent Mono configurations, e.g. due to assembly number version changes or the like.

If someone could check (e.g. by putting the relevant subset of the code through F# Interactive) that would be great.

[0xmohit]

It might be that this code is now failing for some reason on recent Mono configurations, e.g. due to assembly number version changes or the like.

Compiling with FSharp_DebugSetFilePermissions set, i.e. by saying

    FSharp_DebugSetFilePermissions=1 fsharpc a.fs

yields:

F# Compiler for F# 4.0 (Open Source Edition)
Freely distributed under the Apache 2.0 Open Source License
loading type Mono.Unix.UnixFileInfo...
failure: System.MissingMethodException: Method 'Mono.Unix.UnixFileSystemInfo.set_FileAccessPermissions' not found.
  at System.RuntimeType.InvokeMember (System.String name, BindingFlags bindingFlags, System.Reflection.Binder binder, System.Object target, System.Object[] providedArgs, System.Reflection.ParameterModifier[] modifiers, System.Globalization.CultureInfo culture, System.String[] namedParams) <0x7f7f247f8190 + 0x015d6> in <filename unknown>:0 
  at System.Type.InvokeMember (System.String name, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object target, System.Object[] args, System.Globalization.CultureInfo culture) <0x7f7f248c8810 + 0x0005e> in <filename unknown>:0 
  at Microsoft.FSharp.Compiler.AbstractIL.ILBinaryWriter+FileSystemUtilites.setExecutablePermission[a] (a filename) <0x403fb700 + 0x002a8> in <filename unknown>:0 ...

[dsyme]

Ok, well, that's the problem certainly. But I don't understand why that reflection call is now failing. Calling the getter property succeeds, and the setter is public https://github.com/mono/mono/blob/master/mcs/class/Mono.Posix/Mono.Unix/UnixFileSystemInfo.cs#L134

It could be that the argument to the setter method is considered a boxed Int32 instead of a boxed FileAccessPermissions enumeration, and the reflection machinery is no longer applying an auto-conversion. But that would be a strange breaking change in reflection. Still, it's the only explanation I can think of.

If someone would like to trial a fix that would be great.

[dsyme]

Fixed by dotnet/fsharp#2950