remove extrema definition that is no longer needed for bootstrapping (#46592)

* remove extrema definition that is no longer needed for bootstrapping

Author: LilithHafner

base/compiler/compiler.jl

@@ -166,21 +166,6 @@ include("compiler/abstractinterpretation.jl")
 include("compiler/typeinfer.jl")
 include("compiler/optimize.jl")
 
-# required for bootstrap because sort.jl uses extrema
-# to decide whether to dispatch to counting sort.
-#
-# TODO: remove it.
-function extrema(x::Array)
-    isempty(x) && throw(ArgumentError("collection must be non-empty"))
-    vmin = vmax = x[1]
-    for i in 2:length(x)
-        xi = x[i]
-        vmax = max(vmax, xi)
-        vmin = min(vmin, xi)
-    end
-    return vmin, vmax
-end
-
 include("compiler/bootstrap.jl")
 ccall(:jl_set_typeinf_func, Cvoid, (Any,), typeinf_ext_toplevel)
 

test/reduce.jl

@@ -263,7 +263,6 @@ let x = [4,3,5,2]
     @test maximum(x) == 5
     @test minimum(x) == 2
     @test extrema(x) == (2, 5)
-    @test Core.Compiler.extrema(x) == (2, 5)
 
     @test maximum(abs2, x) == 25
     @test minimum(abs2, x) == 4