This patch backports part of Julia upstream commit:

    1e5fdb29f8858f3244f6aff116ee12e4c8247f3a
    Author:     Simon Byrne <simon.byrne@gmail.com>
    AuthorDate: Tue Jan 10 14:52:36 2023 -0800
    Commit:     GitHub <noreply@github.com>
    CommitDate: Tue Jan 10 17:52:36 2023 -0500

    update MPFR to 4.2.0 (#48165)

    Co-authored-by: Mosè Giordano <giordano@users.noreply.github.com>

    6 files changed, 112 insertions(+), 79 deletions(-)
    base/mpfr.jl                     | 34 ++++++++++++++--
    deps/checksums/mpfr              | 68 ++++++++++++++++----------------
    deps/mpfr.version                |  2 +-
    stdlib/MPFR_jll/Project.toml     |  2 +-
    stdlib/MPFR_jll/test/runtests.jl |  2 +-
    test/math.jl                     | 83 +++++++++++++++++++++-------------------


diff -ur julia-1.8.3-orig/base/mpfr.jl julia-1.8.3-patch/base/mpfr.jl
--- julia-1.8.3-orig/base/mpfr.jl	2023-04-13 17:50:58.394891391 +0200
+++ julia-1.8.3-patch/base/mpfr.jl	2023-04-13 20:42:52.551833467 +0200
@@ -16,7 +16,8 @@
         cosh, sinh, tanh, sech, csch, coth, acosh, asinh, atanh, lerpi,
         cbrt, typemax, typemin, unsafe_trunc, floatmin, floatmax, rounding,
         setrounding, maxintfloat, widen, significand, frexp, tryparse, iszero,
-        isone, big, _string_n, decompose
+        isone, big, _string_n, decompose, minmax,
+        sinpi, cospi, sincospi, sind, cosd, tand, asind, acosd, atand
 
 import ..Rounding: rounding_raw, setrounding_raw
 
@@ -745,7 +746,7 @@
 end
 
 # Functions for which NaN results are converted to DomainError, following Base
-for f in (:sin, :cos, :tan, :sec, :csc, :acos, :asin, :atan, :acosh, :asinh, :atanh)
+for f in (:sin, :cos, :tan, :sec, :csc, :acos, :asin, :atan, :acosh, :asinh, :atanh, :sinpi, :cospi)
     @eval begin
         function ($f)(x::BigFloat)
             isnan(x) && return x
@@ -756,6 +757,7 @@
         end
     end
 end
+sincospi(x::BigFloat) = (sinpi(x), cospi(x))
 
 function atan(y::BigFloat, x::BigFloat)
     z = BigFloat()
@@ -763,6 +765,32 @@
     return z
 end
 
+# degree functions
+for f in (:sin, :cos, :tan)
+    @eval begin
+        function ($(Symbol(f,:d)))(x::BigFloat)
+            isnan(x) && return x
+            z = BigFloat()
+            ccall(($(string(:mpfr_,f,:u)), :libmpfr), Int32, (Ref{BigFloat}, Ref{BigFloat}, Culong, MPFRRoundingMode), z, x, 360, ROUNDING_MODE[])
+            isnan(z) && throw(DomainError(x, "NaN result for non-NaN input."))
+            return z
+        end
+        function ($(Symbol(:a,f,:d)))(x::BigFloat)
+            isnan(x) && return x
+            z = BigFloat()
+            ccall(($(string(:mpfr_a,f,:u)), :libmpfr), Int32, (Ref{BigFloat}, Ref{BigFloat}, Culong, MPFRRoundingMode), z, x, 360, ROUNDING_MODE[])
+            isnan(z) && throw(DomainError(x, "NaN result for non-NaN input."))
+            return z
+        end
+    end
+end
+function atand(y::BigFloat, x::BigFloat)
+    z = BigFloat()
+    ccall((:mpfr_atan2u, :libmpfr), Int32, (Ref{BigFloat}, Ref{BigFloat}, Ref{BigFloat}, Culong, MPFRRoundingMode), z, y, x, 360, ROUNDING_MODE[])
+    return z
+end
+
+
 # Utility functions
 ==(x::BigFloat, y::BigFloat) = ccall((:mpfr_equal_p, :libmpfr), Int32, (Ref{BigFloat}, Ref{BigFloat}), x, y) != 0
 <=(x::BigFloat, y::BigFloat) = ccall((:mpfr_lessequal_p, :libmpfr), Int32, (Ref{BigFloat}, Ref{BigFloat}), x, y) != 0
@@ -1018,7 +1046,7 @@
     isfinite(x) || return string(Float64(x))
     _prettify_bigfloat(string_mpfr(x, fmt))
 end
-_string(x::BigFloat) = _string(x, "%.Re")
+_string(x::BigFloat) = _string(x, "%Re")
 _string(x::BigFloat, k::Integer) = _string(x, "%.$(k)Re")
 
 string(b::BigFloat) = _string(b)
diff -ur julia-1.8.3-orig/test/math.jl julia-1.8.3-patch/test/math.jl
--- julia-1.8.3-orig/test/math.jl	2023-04-13 17:50:58.382891276 +0200
+++ julia-1.8.3-patch/test/math.jl	2023-04-13 21:13:55.377279761 +0200
@@ -411,47 +411,51 @@
     @test rad2deg(pi + (pi/3)*im) ≈ 180 + 60im
 end
 
+# ensure zeros are signed the same
+⩲(x,y) = typeof(x) == typeof(y) && x == y && signbit(x) == signbit(y)
+⩲(x::Tuple, y::Tuple) = length(x) == length(y) && all(map(⩲,x,y))
+
 @testset "degree-based trig functions" begin
-    @testset "$T" for T = (Float32,Float64,Rational{Int})
+    @testset "$T" for T = (Float32,Float64,Rational{Int},BigFloat)
         fT = typeof(float(one(T)))
         fTsc = typeof( (float(one(T)), float(one(T))) )
         for x = -400:40:400
-            @test sind(convert(T,x))::fT ≈ convert(fT,sin(pi/180*x)) atol=eps(deg2rad(convert(fT,x)))
-            @test cosd(convert(T,x))::fT ≈ convert(fT,cos(pi/180*x)) atol=eps(deg2rad(convert(fT,x)))
+            @test sind(convert(T,x))::fT ≈ sin(pi*convert(fT,x)/180) atol=eps(deg2rad(convert(fT,x)))
+            @test cosd(convert(T,x))::fT ≈ cos(pi*convert(fT,x)/180) atol=eps(deg2rad(convert(fT,x)))
 
             s,c = sincosd(convert(T,x))
-            @test s::fT ≈ convert(fT,sin(pi/180*x)) atol=eps(deg2rad(convert(fT,x)))
-            @test c::fT ≈ convert(fT,cos(pi/180*x)) atol=eps(deg2rad(convert(fT,x)))
+            @test s::fT ≈ sin(pi*convert(fT,x)/180) atol=eps(deg2rad(convert(fT,x)))
+            @test c::fT ≈ cos(pi*convert(fT,x)/180) atol=eps(deg2rad(convert(fT,x)))
         end
         @testset "sind" begin
-            @test sind(convert(T,0.0))::fT === zero(fT)
-            @test sind(convert(T,180.0))::fT === zero(fT)
-            @test sind(convert(T,360.0))::fT === zero(fT)
-            T != Rational{Int} && @test sind(convert(T,-0.0))::fT === -zero(fT)
-            @test sind(convert(T,-180.0))::fT === -zero(fT)
-            @test sind(convert(T,-360.0))::fT === -zero(fT)
+            @test sind(convert(T,0.0))::fT ⩲ zero(fT)
+            @test sind(convert(T,180.0))::fT ⩲ zero(fT)
+            @test sind(convert(T,360.0))::fT ⩲ zero(fT)
+            T != Rational{Int} && @test sind(convert(T,-0.0))::fT ⩲ -zero(fT)
+            @test sind(convert(T,-180.0))::fT ⩲ -zero(fT)
+            @test sind(convert(T,-360.0))::fT ⩲ -zero(fT)
             if T <: AbstractFloat
                 @test isnan(sind(T(NaN)))
             end
         end
         @testset "cosd" begin
-            @test cosd(convert(T,90))::fT === zero(fT)
-            @test cosd(convert(T,270))::fT === zero(fT)
-            @test cosd(convert(T,-90))::fT === zero(fT)
-            @test cosd(convert(T,-270))::fT === zero(fT)
+            @test cosd(convert(T,90))::fT ⩲ zero(fT)
+            @test cosd(convert(T,270))::fT ⩲ zero(fT)
+            @test cosd(convert(T,-90))::fT ⩲ zero(fT)
+            @test cosd(convert(T,-270))::fT ⩲ zero(fT)
             if T <: AbstractFloat
                 @test isnan(cosd(T(NaN)))
             end
         end
         @testset "sincosd" begin
-            @test sincosd(convert(T,-360))::fTsc === ( -zero(fT),  one(fT) )
-            @test sincosd(convert(T,-270))::fTsc === (   one(fT), zero(fT) )
-            @test sincosd(convert(T,-180))::fTsc === ( -zero(fT), -one(fT) )
-            @test sincosd(convert(T, -90))::fTsc === (  -one(fT), zero(fT) )
-            @test sincosd(convert(T,   0))::fTsc === (  zero(fT),  one(fT) )
-            @test sincosd(convert(T,  90))::fTsc === (   one(fT), zero(fT) )
-            @test sincosd(convert(T, 180))::fTsc === (  zero(fT), -one(fT) )
-            @test sincosd(convert(T, 270))::fTsc === (  -one(fT), zero(fT) )
+            @test sincosd(convert(T,-360))::fTsc ⩲ ( -zero(fT),  one(fT) )
+            @test sincosd(convert(T,-270))::fTsc ⩲ (   one(fT), zero(fT) )
+            @test sincosd(convert(T,-180))::fTsc ⩲ ( -zero(fT), -one(fT) )
+            @test sincosd(convert(T, -90))::fTsc ⩲ (  -one(fT), zero(fT) )
+            @test sincosd(convert(T,   0))::fTsc ⩲ (  zero(fT),  one(fT) )
+            @test sincosd(convert(T,  90))::fTsc ⩲ (   one(fT), zero(fT) )
+            @test sincosd(convert(T, 180))::fTsc ⩲ (  zero(fT), -one(fT) )
+            @test sincosd(convert(T, 270))::fTsc ⩲ (  -one(fT), zero(fT) )
             if T <: AbstractFloat
                 @test_throws DomainError sincosd(T(Inf))
                 @test all(isnan.(sincosd(T(NaN))))
@@ -463,22 +467,22 @@
             "sincospi" => (x->sincospi(x)[1], x->sincospi(x)[2])
         )
             @testset "pi * $x" for x = -3:0.3:3
-                @test sinpi(convert(T,x))::fT ≈ convert(fT,sin(pi*x)) atol=eps(pi*convert(fT,x))
-                @test cospi(convert(T,x))::fT ≈ convert(fT,cos(pi*x)) atol=eps(pi*convert(fT,x))
+                @test sinpi(convert(T,x))::fT ≈ sin(pi*convert(fT,x)) atol=eps(pi*convert(fT,x))
+                @test cospi(convert(T,x))::fT ≈ cos(pi*convert(fT,x)) atol=eps(pi*convert(fT,x))
             end
 
-            @test sinpi(convert(T,0.0))::fT === zero(fT)
-            @test sinpi(convert(T,1.0))::fT === zero(fT)
-            @test sinpi(convert(T,2.0))::fT === zero(fT)
-            T != Rational{Int} && @test sinpi(convert(T,-0.0))::fT === -zero(fT)
-            @test sinpi(convert(T,-1.0))::fT === -zero(fT)
-            @test sinpi(convert(T,-2.0))::fT === -zero(fT)
+            @test sinpi(convert(T,0.0))::fT ⩲ zero(fT)
+            @test sinpi(convert(T,1.0))::fT ⩲ zero(fT)
+            @test sinpi(convert(T,2.0))::fT ⩲ zero(fT)
+            T != Rational{Int} && @test sinpi(convert(T,-0.0))::fT ⩲ -zero(fT)
+            @test sinpi(convert(T,-1.0))::fT ⩲ -zero(fT)
+            @test sinpi(convert(T,-2.0))::fT ⩲ -zero(fT)
             @test_throws DomainError sinpi(convert(T,Inf))
 
-            @test cospi(convert(T,0.5))::fT === zero(fT)
-            @test cospi(convert(T,1.5))::fT === zero(fT)
-            @test cospi(convert(T,-0.5))::fT === zero(fT)
-            @test cospi(convert(T,-1.5))::fT === zero(fT)
+            @test cospi(convert(T,0.5))::fT ⩲ zero(fT)
+            @test cospi(convert(T,1.5))::fT ⩲ zero(fT)
+            @test cospi(convert(T,-0.5))::fT ⩲ zero(fT)
+            @test cospi(convert(T,-1.5))::fT ⩲ zero(fT)
             @test_throws DomainError cospi(convert(T,Inf))
         end
         @testset "Check exact values" begin
@@ -489,8 +493,8 @@
             @test sincospi(one(T)/convert(T,6))[1] == 0.5
             @test_throws DomainError sind(convert(T,Inf))
             @test_throws DomainError cosd(convert(T,Inf))
-            T != Float32 && @test cospi(one(T)/convert(T,3)) == 0.5
-            T != Float32 && @test sincospi(one(T)/convert(T,3))[2] == 0.5
+            fT == Float64 && @test isapprox(cospi(one(T)/convert(T,3)), 0.5)
+            fT == Float64 && @test isapprox(sincospi(one(T)/convert(T,3))[2], 0.5)
             T == Rational{Int} && @test sinpi(5//6) == 0.5
             T == Rational{Int} && @test sincospi(5//6)[1] == 0.5
         end
@@ -538,8 +542,8 @@
             end
         end
     end
-    @test @inferred(sinc(0//1)) === 1.0
-    @test @inferred(cosc(0//1)) === -0.0
+    @test @inferred(sinc(0//1)) ⩲ 1.0
+    @test @inferred(cosc(0//1)) ⩲ -0.0
 
     # test right before/after thresholds of Taylor series
     @test sinc(0.001) ≈ 0.999998355066745 rtol=1e-15