fix compatible_vatuple

Seemingly `vab` has been computed wrongly.
JuliaLang · Jun 28, 2023 · 25e9bd3 · 25e9bd3
1 parent 196956d
commit 25e9bd3
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Showing 2 changed files with 11 additions and 5 deletions.
diff --git a/base/compiler/typeutils.jl b/base/compiler/typeutils.jl
@@ -139,12 +139,12 @@ valid_tparam(@nospecialize(x)) = valid_typeof_tparam(typeof(x))
 
 function compatible_vatuple(a::DataType, b::DataType)
  vaa = a.parameters[end]
- vab = a.parameters[end]
+ vab = b.parameters[end]
  if !(isvarargtype(vaa) && isvarargtype(vab))
  return isvarargtype(vaa) == isvarargtype(vab)
  end
- (isdefined(vaa, :N) == isdefined(vab, :N)) || return false
- !isdefined(vaa, :N) && return true
+ isdefined(vaa, :N) || return !isdefined(vab, :N)
+ isdefined(vab, :N) || return false
  return vaa.N === vab.N
 end
 
@@ -163,8 +163,7 @@ function typesubtract(@nospecialize(a), @nospecialize(b), max_union_splitting::I
  elseif a isa DataType
  ub = unwrap_unionall(b)
  if ub isa DataType
- if a.name === ub.name === Tuple.name &&
- length(a.parameters) == length(ub.parameters)
+ if a.name === ub.name === Tuple.name && length(a.parameters) == length(ub.parameters)
  if 1 < unionsplitcost(JLTypeLattice(), a.parameters) <= max_union_splitting
  ta = switchtupleunion(a)
  return typesubtract(Union{ta...}, b, 0)

diff --git a/test/compiler/inference.jl b/test/compiler/inference.jl
@@ -3499,9 +3499,16 @@ end
  Tuple{Int, Char, Int}, Tuple{Int, Int, Char}, Tuple{Int, Int, Int}}
 # Test that these don't throw
 @test Core.Compiler.typesubtract(Tuple{Vararg{Int}}, Tuple{Vararg{Char}}, 0) == Tuple{Vararg{Int}}
+@test Core.Compiler.typesubtract(Tuple{Vararg{Int}}, Tuple{Vararg{Int}}, 0) == Union{}
+@test Core.Compiler.typesubtract(Tuple{String,Int}, Tuple{String,Vararg{Int}}, 0) == Union{}
+@test Core.Compiler.typesubtract(Tuple{String,Vararg{Int}}, Tuple{String,Int}, 0) == Tuple{String,Vararg{Int}}
 @test Core.Compiler.typesubtract(NTuple{3, Real}, NTuple{3, Char}, 0) == NTuple{3, Real}
 @test Core.Compiler.typesubtract(NTuple{3, Union{Real, Char}}, NTuple{2, Char}, 0) == NTuple{3, Union{Real, Char}}
 
+@test Core.Compiler.compatible_vatuple(Tuple{String,Vararg{Int}}, Tuple{String,Vararg{Int}})
+@test !Core.Compiler.compatible_vatuple(Tuple{String,Int}, Tuple{String,Vararg{Int}})
+@test !Core.Compiler.compatible_vatuple(Tuple{String,Vararg{Int}}, Tuple{String,Int})
+
 @test Base.return_types(Issue35566.f) == [Val{:expected}]
 
 # constant prop through keyword arguments