effects: Mark _typevar CONSISTENT_IF_NOTRETURNED

Like other mutable allocation consistency here is flow-dependent.
JuliaLang · Jan 9, 2023 · a90405f · a90405f
1 parent 60a4479
commit a90405f
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Showing 2 changed files with 8 additions and 2 deletions.
diff --git a/base/compiler/tfuncs.jl b/base/compiler/tfuncs.jl
@@ -2245,7 +2245,8 @@ function builtin_effects(𝕃::AbstractLattice, @nospecialize(f::Builtin), argty
         effect_free = get_binding_type_effect_free(argtypes[1], argtypes[2]) ? ALWAYS_TRUE : ALWAYS_FALSE
         return Effects(EFFECTS_TOTAL; effect_free)
     else
-        consistent = contains_is(_CONSISTENT_BUILTINS, f) ? ALWAYS_TRUE : ALWAYS_FALSE
+        consistent = contains_is(_CONSISTENT_BUILTINS, f) ? ALWAYS_TRUE :
+            (f === Core._typevar) ? CONSISTENT_IF_NOTRETURNED : ALWAYS_FALSE
         if f === setfield! || f === arrayset
             effect_free = EFFECT_FREE_IF_INACCESSIBLEMEMONLY
         elseif contains_is(_EFFECT_FREE_BUILTINS, f) || contains_is(_PURE_BUILTINS, f)

diff --git a/test/compiler/effects.jl b/test/compiler/effects.jl
@@ -687,4 +687,9 @@ end |> Core.Compiler.is_total
 @test Base.infer_effects(Tuple{WrapperOneField{Float64}, Symbol}) do w, s
     getfield(w, s)
 end |> Core.Compiler.is_foldable
-@test Core.Compiler.getfield_notundefined(WrapperOneField{Float64}, Symbol)
+@test Core.Compiler.getfield_notundefined(WrapperOneField{Float64}, Symbol)
+
+# Flow-sensitive consistenct for _typevar
+@test Base.infer_effects() do
+    return WrapperOneField == (WrapperOneField{T} where T)
+end |> Core.Compiler.is_total