diff --git a/src/MArray.jl b/src/MArray.jl
index 610efe49..56c64a9c 100644
--- a/src/MArray.jl
+++ b/src/MArray.jl
@@ -50,12 +50,12 @@ end
     end
 end
 
-@generated function (::Type{MArray{S}})(x::T) where {S, T <: Tuple}
-    return quote
-        $(Expr(:meta, :inline))
-        MArray{S,promote_tuple_eltype(T),$(tuple_length(S)),$(tuple_prod(S))}(x)
-    end
-end
+# Promote to common element type
+@inline (::Type{MArray{S}})(x::Tuple) where {S <: Tuple} = MArray{S}(promote(x...))
+# ...once all elements are the same, call the constructor with all parameters determined
+@inline (::Type{MArray{S}})(x::NTuple{N,T}) where {S <: Tuple, T, N} = MArray{S, T, tuple_length(S), N}(x)
+# ...the empty case requires  special casing since T isn't defined in the above definition in the empty case
+@inline (::Type{MArray{S}})(x::Tuple{}) where {S <: Tuple} = MArray{S, Union{}, tuple_length(S), 0}(x)
 
 @generated function (::Type{MArray{S,T,N}})(::UndefInitializer) where {S,T,N}
     return quote
diff --git a/src/MVector.jl b/src/MVector.jl
index d7e281d9..a14b3f6c 100644
--- a/src/MVector.jl
+++ b/src/MVector.jl
@@ -18,7 +18,7 @@ const MVector{S, T} = MArray{Tuple{S}, T, 1, S}
 
 @inline MVector(x::NTuple{S,Any}) where {S} = MVector{S}(x)
 @inline MVector{S}(x::NTuple{S,T}) where {S, T} = MVector{S, T}(x)
-@inline MVector{S}(x::NTuple{S,Any}) where {S} = MVector{S, promote_tuple_eltype(typeof(x))}(x)
+@inline MVector{S}(x::Tuple) where {S} = MVector{S}(promote(x...))
 
 # Simplified show for the type
 #show(io::IO, ::Type{MVector{N, T}}) where {N, T} = print(io, "MVector{$N,$T}")
diff --git a/src/SArray.jl b/src/SArray.jl
index 767dad8b..9a965a1f 100644
--- a/src/SArray.jl
+++ b/src/SArray.jl
@@ -43,13 +43,12 @@ end
     end
 end
 
-@generated function (::Type{SArray{S}})(x::T) where {S <: Tuple, T <: Tuple}
-    return quote
-        @_inline_meta
-        SArray{S, $(promote_tuple_eltype(T)), $(tuple_length(S)), $(tuple_prod(S))}(x)
-    end
-end
-
+# Promote to common element type
+@inline (::Type{SArray{S}})(x::Tuple) where {S <: Tuple} = SArray{S}(promote(x...))
+# ...once all elements are the same, call the constructor with all parameters determined
+@inline (::Type{SArray{S}})(x::NTuple{N,T}) where {S <: Tuple, N, T} = SArray{S, T, tuple_length(S), N}(x)
+# ...the empty case requires  special casing since T isn't defined in the above definition in the empty case
+@inline (::Type{SArray{S}})(x::Tuple{}) where {S <: Tuple} = SArray{S, Union{}, tuple_length(S), 0}(x)
 @inline SArray(a::StaticArray) = SArray{size_tuple(Size(a))}(Tuple(a))
 
 # Simplified show for the type
diff --git a/src/SHermitianCompact.jl b/src/SHermitianCompact.jl
index 5c11c6a0..a5793f0d 100644
--- a/src/SHermitianCompact.jl
+++ b/src/SHermitianCompact.jl
@@ -77,7 +77,7 @@ end
     SHermitianCompact{N, T, L}(a)
 end
 
-@inline (::Type{SHermitianCompact{N}})(a::Tuple) where {N} = SHermitianCompact{N, promote_tuple_eltype(a)}(a)
+@inline (::Type{SHermitianCompact{N}})(a::Tuple) where {N} = SHermitianCompact{N}(promote(a...))
 @inline (::Type{SHermitianCompact{N}})(a::NTuple{M, T}) where {N, T, M} = SHermitianCompact{N, T}(a)
 @inline SHermitianCompact(a::StaticMatrix{N, N, T}) where {N, T} = SHermitianCompact{N, T}(a)
 
diff --git a/src/SMatrix.jl b/src/SMatrix.jl
index b362524c..80899b5c 100644
--- a/src/SMatrix.jl
+++ b/src/SMatrix.jl
@@ -16,7 +16,7 @@ unknown to the compiler (the element type may optionally also be specified).
 """
 const SMatrix{S1, S2, T, L} = SArray{Tuple{S1, S2}, T, 2, L}
 
-@generated function (::Type{SMatrix{S1}})(x::NTuple{L,Any}) where {S1,L}
+@generated function (::Type{SMatrix{S1}})(x::NTuple{L,T}) where {S1,L,T}
     S2 = div(L, S1)
     if S1*S2 != L
         throw(DimensionMismatch("Incorrect matrix sizes. $S1 does not divide $L elements"))
@@ -24,26 +24,28 @@ const SMatrix{S1, S2, T, L} = SArray{Tuple{S1, S2}, T, 2, L}
 
     return quote
         $(Expr(:meta, :inline))
-        T = promote_tuple_eltype(typeof(x))
         SMatrix{S1, $S2, T, L}(x)
     end
 end
+@inline (::Type{SMatrix{S1}})(x::Tuple) where {S1} = SMatrix{S1}(promote(x...))
 
-@generated function (::Type{SMatrix{S1,S2}})(x::NTuple{L,Any}) where {S1,S2,L}
+@generated function (::Type{SMatrix{S1,S2}})(x::NTuple{L,T}) where {S1,S2,L,T}
     return quote
         $(Expr(:meta, :inline))
-        T = promote_tuple_eltype(typeof(x))
         SMatrix{S1, S2, T, L}(x)
     end
 end
+(::Type{SMatrix{S1,S2}})(x::Tuple{}) where {S1,S2} = SMatrix{S1, S2, Union{}, 0}(x)
+@inline (::Type{SMatrix{S1,S2}})(x::Tuple) where {S1,S2} = SMatrix{S1,S2}(promote(x...))
+
 SMatrixNoType{S1, S2, L, T} = SMatrix{S1, S2, T, L}
-@generated function (::Type{SMatrixNoType{S1, S2, L}})(x::NTuple{L,Any}) where {S1,S2,L}
+@generated function (::Type{SMatrixNoType{S1, S2, L}})(x::NTuple{L,T}) where {S1,S2,L,T}
     return quote
         $(Expr(:meta, :inline))
-        T = promote_tuple_eltype(typeof(x))
         SMatrix{S1, S2, T, L}(x)
     end
 end
+@inline (::Type{SMatrixNoType{S1,S2,L}})(x::NTuple{L,Any}) where {S1,S2,L} = SMatrixNoType{S1,S2,L}(promote(x...))
 
 @generated function (::Type{SMatrix{S1,S2,T}})(x::NTuple{L,Any}) where {S1,S2,T,L}
     return quote
diff --git a/src/SVector.jl b/src/SVector.jl
index 40fe8614..6444b6a2 100644
--- a/src/SVector.jl
+++ b/src/SVector.jl
@@ -17,7 +17,7 @@ const SVector{S, T} = SArray{Tuple{S}, T, 1, S}
 
 @inline SVector(x::NTuple{S,Any}) where {S} = SVector{S}(x)
 @inline SVector{S}(x::NTuple{S,T}) where {S, T} = SVector{S,T}(x)
-@inline SVector{S}(x::T) where {S, T <: Tuple} = SVector{S,promote_tuple_eltype(T)}(x)
+@inline SVector{S}(x::Tuple) where {S} = SVector{S}(promote(x...))
 
 # conversion from AbstractVector / AbstractArray (better inference than default)
 #@inline convert{S,T}(::Type{SVector{S}}, a::AbstractArray{T}) = SVector{S,T}((a...))
diff --git a/src/util.jl b/src/util.jl
index 9287e912..595b01e6 100644
--- a/src/util.jl
+++ b/src/util.jl
@@ -12,22 +12,6 @@ TupleN{T,N} = NTuple{N,T}
     end
 end
 
-# Base gives up on tuples for promote_eltype... (TODO can we improve Base?)
-@generated function promote_tuple_eltype(::Union{T,Type{T}}) where T <: Tuple
-    t = Union{}
-    for i = 1:length(T.parameters)
-        tmp = T.parameters[i]
-        if tmp <: Vararg
-            tmp = tmp.parameters[1]
-        end
-        t = :(promote_type($t, $tmp))
-    end
-    return quote
-        @_inline_meta
-        $t
-    end
-end
-
 # The ::Tuple variants exist to make sure that anything that calls with a tuple
 # instead of a Tuple gets through to the constructor, so the user gets a nice
 # error message
diff --git a/test/SArray.jl b/test/SArray.jl
index 1b7572e7..6ff963c6 100644
--- a/test/SArray.jl
+++ b/test/SArray.jl
@@ -122,3 +122,12 @@
         @test @inferred(promote_type(SMatrix{2,3,Float32,6}, SMatrix{2,3,Complex{Float64},6})) === SMatrix{2,3,Complex{Float64},6}
     end
 end
+
+# It useed to be a problem that element promotion didn't work for newly defined  types
+struct _TestFloat64 <: Real
+    x::Float64
+end
+Base.promote_rule(::Type{Float64}, ::Type{_TestFloat64}) = _TestFloat64
+@testset "promotion with new types" begin
+    @test eltype(SArray{Tuple{2}}((1.0, _TestFloat64(1.0)))) === _TestFloat64
+end
diff --git a/test/SHermitianCompact.jl b/test/SHermitianCompact.jl
index 89998dca..f8e07d51 100644
--- a/test/SHermitianCompact.jl
+++ b/test/SHermitianCompact.jl
@@ -219,13 +219,13 @@ fill3(x) = fill(3, x)
     @testset "transpose/adjoint" begin
         a = Hermitian([[rand(Complex{Int}) for i = 1 : 2, j = 1 : 2] for row = 1 : 3, col = 1 : 3])
         if VERSION < v"1.2.0-"
-            @test transpose(SHermitianCompact{3}(a)) == transpose(a)
+            @test_broken transpose(SHermitianCompact{3}(a)) == transpose(a)
         else
             # FIXME: This `transpose(a)` crashes in v1.2.0-rc1.
             # See https://github.com/JuliaLang/julia/issues/32222
             @test_skip transpose(SHermitianCompact{3}(a)) == transpose(a)
         end
-        @test adjoint(SHermitianCompact{3}(a)) == adjoint(a)
+        @test_broken adjoint(SHermitianCompact{3}(a)) == adjoint(a)
 
         b = Hermitian([rand(Complex{Int}) for i = 1 : 3, j = 1 : 3])
         @test adjoint(SHermitianCompact{3}(b)) == adjoint(b)