isbits-unions: is and object_id predicates were looking at undefi…

…ned data

src/builtins.c

@@ -103,7 +103,7 @@ static int NOINLINE compare_fields(jl_value_t *a, jl_value_t *b, jl_datatype_t *
  ft = (jl_datatype_t*)jl_nth_union_component((jl_value_t*)ft, asel);
  }
  if (!ft->layout->haspadding) {
- if (!bits_equal(ao, bo, jl_field_size(dt, f)))
+ if (!bits_equal(ao, bo, ft->size))
  return 0;
  }
  else {
@@ -337,7 +337,7 @@ static uintptr_t jl_object_id_(jl_value_t *tv, jl_value_t *v)
  if (fieldtype->layout->haspadding)
  u = jl_object_id_((jl_value_t*)fieldtype, (jl_value_t*)vo);
  else
- u = bits_hash(vo, jl_field_size(dt, f));
+ u = bits_hash(vo, fieldtype->size);
  }
  h = bitmix(h, u);
  }

test/core.jl

@@ -5576,16 +5576,20 @@ initvalue2(::Type{T}) where {T <: Number} = T(1)
 
 U = unboxedunions[1]
 
+@noinline compare(a, b) = (a === b) # make sure we are testing code-generation of `is`
+egal(x, y) = (ccall(:jl_egal, Cint, (Any, Any), x, y) != 0) # make sure we are NOT testing code-generate of `is`
+
 mutable struct UnionField
  u::U
 end
 
-x = UnionField(initvalue(Base.uniontypes(U)[1]))
-@test x.u === initvalue(Base.uniontypes(U)[1])
-x.u = initvalue2(Base.uniontypes(U)[1])
-@test x.u === initvalue2(Base.uniontypes(U)[1])
-x.u = initvalue(Base.uniontypes(U)[2])
-@test x.u === initvalue(Base.uniontypes(U)[2])
+let x = UnionField(initvalue(Base.uniontypes(U)[1]))
+ @test x.u === initvalue(Base.uniontypes(U)[1])
+ x.u = initvalue2(Base.uniontypes(U)[1])
+ @test x.u === initvalue2(Base.uniontypes(U)[1])
+ x.u = initvalue(Base.uniontypes(U)[2])
+ @test x.u === initvalue(Base.uniontypes(U)[2])
+end
 
 mutable struct UnionField2
  x::Union{Nothing, Int}
@@ -5613,10 +5617,12 @@ let x4 = UnionField4(nothing, Int8(3))
  @test x4.x === nothing
  @test x4.y === Int8(3)
  @test x4.z[1] === 0x11
- @test x4 === x4
+ @test compare(x4, x4)
  @test x4 == x4
+ @test egal(x4, x4)
  @test !(x4 === x4copy)
  @test !(x4 == x4copy)
+ @test !egal(x4, x4copy)
 end
 
 struct UnionField5
@@ -5633,10 +5639,11 @@ let x5 = UnionField5(nothing, Int8(3))
  @test x5.x === nothing
  @test x5.y === Int8(3)
  @test x5.z[1] === 0x11
- @test x5 === x5
+ @test compare(x5, x5)
  @test x5 == x5
- @test x5 === x5copy
+ @test compare(x5, x5copy)
  @test x5 == x5copy
+ @test egal(x5, x5copy)
  @test objectid(x5) === objectid(x5copy)
  @test hash(x5) === hash(x5copy)
 end
@@ -5651,7 +5658,6 @@ struct B23367
  y::A23367
  z::Int8
 end
-@noinline compare(a, b) = (a === b) # test code-generation of `is`
 @noinline get_x(a::A23367) = a.x
 function constant23367 end
 let
@@ -5665,9 +5671,9 @@ let
  @test addr(b) != addr(b3)
  @test addr(b2) != addr(b3)
 
- @test b === b2 === b3
- @test compare(b, b2)
- @test compare(b, b3)
+ @test b === b2 === b3 === b
+ @test egal(b, b2) && egal(b2, b3) && egal(b3, b)
+ @test compare(b, b2) && compare(b, b3) && compare(b2, b3)
  @test objectid(b) === objectid(b2) == objectid(b3)
  @test b.x === Int8(91)
  @test b.z === Int8(23)