Why are the function's arguments optimized out in the case of breakpoint_on_error() ?

[josefsachsconning]

They are not optimized out if I set a breakpoint.

Using master branch of Gallium and its dependencies.

AWS-Sachs-Ubuntu$ usr/bin/julia
               _
   _       _ _(_)_     |  A fresh approach to technical computing
  (_)     | (_) (_)    |  Documentation: http://docs.julialang.org
   _ _   _| |_  __ _   |  Type "?help" for help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 0.5.0-dev+4083 (2016-05-13 15:09 UTC)
 _/ |\__'_|_|_|\__'_|  |  Commit 906e06b (0 days old master)
|__/                   |  x86_64-linux-gnu

julia> using Gallium

julia> function myfunction1(x, y)
           return x + y
       end
myfunction1 (generic function with 1 method)

julia> bp = Gallium.breakpoint(myfunction1)
Locations (+: active, -: inactive, *: source):
 * Any matching method added to #myfunction1
 * Any matching specialization of myfunction1(x, y) at REPL[2]:2


julia> myfunction1(2,3)
In REPL[2]:2
1 function myfunction1(x, y)
2     return x + y
3 end

About to run: Main.+
1|debug > bt
[1] myfunction1(x, y) at REPL[2]:2
  | #self# = <undefined>
  | x::Int64 = 2
  | y::Int64 = 3
[2] eval(m, e) at boot.jl:226
  | #self# = <optimized out>
  | m = <optimized out>
  | e = <optimized out>
[3] eval_user_input(ast, backend) at REPL.jl:50
  | #self# = <optimized out>
  | ast::Expr = myfunction1(2,3)
  | backend = <optimized out>
  | iserr = <optimized out>
  | bt::Void = nothing
  | lasterr::Tuple{} = ()
  | err = <optimized out>
  | ans = <optimized out>
  | value = <optimized out>
[4] #1() at event.jl:46
  | #self# = <optimized out>
  | tls = <optimized out>
  | ast = <optimized out>
  | show_value = <optimized out>

1|debug >
5

julia> Gallium.remove(bp)

julia> Gallium.breakpoint_on_error()
Gallium.Hooking.Hook(Ptr{Void} @0x00007faba703d160,UInt8[0x55,0x48,0x89,0xe5,0x53,0x48,0x89,0xfb,0x48,0x83,0xec,0x08,0xe8,0x6f,0x23,0x02,0x00],Gallium.breakpoint_on_error_hit)

julia> myfunction1(2,"three")
ERROR: MethodError: no method matching +(::Int64, ::String)
Closest candidates are:
  +(::Any, ::Any, ::Any, ::Any...)
  +{T<:Union{Int128,Int16,Int32,Int64,Int8,UInt128,UInt16,UInt32,UInt64,UInt8}}(::T<:Union{Int128,Int16,Int32,Int64,Int8,UInt128,UInt16,UInt32,UInt64,UInt8}, ::T<:Union{Int128,Int16,Int32,Int64,Int8,UInt128,UInt16,UInt32,UInt64,UInt8})
  +(::Integer, ::Ptr{T})
  ...

In REPL[2]:2
1 function myfunction1(x, y)
2     return x + y
3 end

1|debug > bt
[1] myfunction1(x, y) at REPL[2]:2
  | #self# = <optimized out>
  | x = <optimized out>
  | y = <optimized out>
[2] eval(m, e) at boot.jl:226
  | #self# = <optimized out>
  | m = <optimized out>
  | e = <optimized out>
[3] eval_user_input(ast, backend) at REPL.jl:50
  | #self# = <optimized out>
  | ast::Expr = myfunction1(2,"three")
  | backend = <optimized out>
  | iserr = <optimized out>
  | bt::Void = nothing
  | lasterr::Tuple{} = ()
  | err = <optimized out>
  | ans = <optimized out>
  | value = <optimized out>
[4] #1() at event.jl:46
  | #self# = <optimized out>
  | tls = <optimized out>
  | ast = <optimized out>
  | show_value = <optimized out>

1|debug >

[Keno]

Try julia -O0 when using Gallium in order to avoid things being optimized out. The reason that they're not optimized out with regular breakpoints is that argument registers get clobbered by the call to the error function (since the compiler realizes the arguments are no longer needed). I have some plans to improve debug information in non-O0 mode, but that's a long path.