diff --git a/base/dates/types.jl b/base/dates/types.jl
index 4cde4ca353af7..b1e5e437f2dd0 100644
--- a/base/dates/types.jl
+++ b/base/dates/types.jl
@@ -160,4 +160,4 @@ Base.promote_rule(::Type{Date},x::Type{DateTime}) = DateTime
 Base.isless(x::Date,y::Date) = isless(value(x),value(y))
 Base.isless(x::DateTime,y::DateTime) = isless(value(x),value(y))
 Base.isless(x::TimeType,y::TimeType) = isless(promote(x,y)...)
-==(x::TimeType,y::TimeType) = ===(promote(x,y)...)
\ No newline at end of file
+==(x::TimeType,y::TimeType) = ===(promote(x,y)...)
diff --git a/base/int.jl b/base/int.jl
index 85760b852cd2d..58382165d7b7e 100644
--- a/base/int.jl
+++ b/base/int.jl
@@ -43,6 +43,11 @@ abs(x::Signed) = flipsign(x,x)
 
 ~(n::Integer) = -n-1
 
+asunsigned(x::Integer) = reinterpret(typeof(unsigned(zero(x))), x)
+asunsigned(x) = unsigned(x)
+assigned(x::Integer) = reinterpret(typeof(signed(zero(x))), x)
+assigned(x) = signed(x)
+
 div(x::Signed, y::Unsigned) = flipsign(assigned(div(asunsigned(abs(x)),y)),x)
 div(x::Unsigned, y::Signed) = asunsigned(flipsign(assigned(div(x,asunsigned(abs(y)))),y))
 
@@ -132,9 +137,6 @@ for T in IntTypes
     end
 end
 
-asunsigned(x) = reinterpret(typeof(unsigned(zero(x))), x)
-assigned(x) = reinterpret(typeof(signed(zero(x))), x)
-
 ==(x::Signed,   y::Unsigned) = (x >= 0) & (asunsigned(x) == y)
 ==(x::Unsigned, y::Signed  ) = (y >= 0) & (x == asunsigned(y))
 < (x::Signed,   y::Unsigned) = (x <  0) | (asunsigned(x) <  y)
@@ -227,7 +229,8 @@ int32(x) = convert(Int32,x)
 int64(x) = convert(Int64,x)
 int128(x) = convert(Int128,x)
 
-uint8(x) = itrunc(Uint8,x)
+uint8(x) = convert(Uint8, x)
+uint8(x::Integer) = itrunc(Uint8,x)
 uint8(x::Int8) = box(Uint8,unbox(Int8,x))
 uint16(x) = convert(Uint16,x)
 uint32(x) = convert(Uint32,x)
diff --git a/base/range.jl b/base/range.jl
index 6979e3575ffa2..dcda238d4d07f 100644
--- a/base/range.jl
+++ b/base/range.jl
@@ -39,9 +39,9 @@ immutable StepRange{T,S} <: OrdinalRange{T,S}
                 if T<:Signed && (diff > zero(diff)) != (stop > start)
                     # handle overflowed subtraction with unsigned rem
                     if diff > zero(diff)
-                        remain = -oftype(T, unsigned(-diff) % step)
+                        remain = -oftype(T, asunsigned(-diff) % step)
                     else
-                        remain = oftype(T, unsigned(diff) % step)
+                        remain = oftype(T, asunsigned(diff) % step)
                     end
                 else
                     remain = steprem(start,stop,step)
diff --git a/src/intrinsics.cpp b/src/intrinsics.cpp
index 8f0b0b22b25c9..1a135cfee02a0 100644
--- a/src/intrinsics.cpp
+++ b/src/intrinsics.cpp
@@ -424,6 +424,9 @@ static Value *generic_box(jl_value_t *targ, jl_value_t *x, jl_codectx_t *ctx)
     if (vxt != llvmt) {
         if (vxt == T_void)
             return vx;
+        if (!vxt->isSingleValueType()) {
+            jl_error("box: argument not of a primitive type");
+        }
         if (llvmt == T_int1) {
             vx = builder.CreateTrunc(vx, llvmt);
         }
diff --git a/test/dates/types.jl b/test/dates/types.jl
index c9edf562fce30..ea7e71f0ffaaa 100644
--- a/test/dates/types.jl
+++ b/test/dates/types.jl
@@ -63,9 +63,9 @@ test = Dates.Date(1,1,1)
 @test Dates.Date(false,true,true) == test - Dates.Year(1)
 @test_throws ArgumentError Dates.Date(true,true,false)
 @test Dates.Date(uint64(1),uint64(1),uint64(1)) == test
-@test Dates.Date(0xffffffffffffffff,uint64(1),uint64(1)) == test - Dates.Year(2)
+@test Dates.Date(-1,uint64(1),uint64(1)) == test - Dates.Year(2)
 @test Dates.Date(int128(1),int128(1),int128(1)) == test
-@test Dates.Date(170141183460469231731687303715884105727,int128(1),int128(1)) == test - Dates.Year(2)
+@test_throws InexactError Dates.Date(170141183460469231731687303715884105727,int128(1),int128(1))
 @test Dates.Date(uint128(1),uint128(1),uint128(1)) == test
 @test Dates.Date(big(1),big(1),big(1)) == test
 @test Dates.Date(big(1),big(1),big(1)) == test
@@ -171,4 +171,4 @@ ms = Dates.Millisecond(1)
 @test Dates.Date(d,y) == Dates.Date(1,1,1)
 @test Dates.Date(d,m) == Dates.Date(1,1,1)
 @test Dates.Date(m,y) == Dates.Date(1,1,1)
-=#
\ No newline at end of file
+=#