diff --git a/docs/src/pages/api.md b/docs/src/pages/api.md
index 68c76cb7..0e582c4e 100644
--- a/docs/src/pages/api.md
+++ b/docs/src/pages/api.md
@@ -60,7 +60,7 @@ same vector. We can now do this with the `Scalar` type:
 The size of a statically sized array is a static parameter associated with the
 type of the array. The `Size` trait is provided as an abstract representation of
 the dimensions of a static array. An array `sa::SA` of size `(dims...)` is
-associated with `Size{(dims...)}()`. The following are equivalent (`@pure`)
+associated with `Size{(dims...)}()`. The following are equivalent
 constructors:
 ```julia
 Size{(dims...,)}()
diff --git a/src/SHermitianCompact.jl b/src/SHermitianCompact.jl
index ab68ab21..548df21d 100644
--- a/src/SHermitianCompact.jl
+++ b/src/SHermitianCompact.jl
@@ -44,8 +44,8 @@ end
     end
 end
 
-Base.@pure triangularnumber(N::Int) = div(N * (N + 1), 2)
-Base.@pure triangularroot(L::Int) = div(isqrt(8 * L + 1) - 1, 2) # from quadratic formula
+triangularnumber(N::Int) = div(N * (N + 1), 2)
+triangularroot(L::Int) = div(isqrt(8 * L + 1) - 1, 2) # from quadratic formula
 
 lowertriangletype(::Type{SHermitianCompact{N, T, L}}) where {N, T, L} = SVector{L, T}
 lowertriangletype(::Type{SHermitianCompact{N, T}}) where {N, T} = SVector{triangularnumber(N), T}
diff --git a/src/SOneTo.jl b/src/SOneTo.jl
index cec29475..5ef3c9cd 100644
--- a/src/SOneTo.jl
+++ b/src/SOneTo.jl
@@ -38,7 +38,7 @@ end
 Base.first(::SOneTo) = 1
 Base.last(::SOneTo{n}) where {n} = n::Int
 
-@pure function Base.iterate(::SOneTo{n}) where {n}
+function Base.iterate(::SOneTo{n}) where {n}
     if n::Int < 1
         return nothing
     else
@@ -68,7 +68,7 @@ function Base.show(io::IO, ::SOneTo{n}) where {n}
     print(io, "SOneTo(", n::Int, ")")
 end
 
-Base.@pure function Base.checkindex(::Type{Bool}, ::SOneTo{n1}, ::SOneTo{n2}) where {n1, n2}
+function Base.checkindex(::Type{Bool}, ::SOneTo{n1}, ::SOneTo{n2}) where {n1, n2}
     return n1::Int >= n2::Int
 end
 
diff --git a/src/SUnitRange.jl b/src/SUnitRange.jl
index 4661336c..32255887 100644
--- a/src/SUnitRange.jl
+++ b/src/SUnitRange.jl
@@ -6,7 +6,7 @@ struct SUnitRange{Start, L} <: StaticVector{L, Int}
     end
 end
 
-@pure function check_sunitrange_params(L::Int)
+function check_sunitrange_params(L::Int)
     if L < 0
         error("Static unit range length is negative")
     end
@@ -16,9 +16,9 @@ function check_sunitrange_params(L)
     throw(TypeError(:SUnitRange, "type parameters must be `Int`", Tuple{Int,}, Tuple{typeof(L),}))
 end
 
-@pure SUnitRange(a::Int, b::Int) = SUnitRange{a, max(0, b - a + 1)}()
+SUnitRange(a::Int, b::Int) = SUnitRange{a, max(0, b - a + 1)}()
 
-@pure @propagate_inbounds function getindex(x::SUnitRange{Start, L}, i::Int) where {Start, L}
+@propagate_inbounds function getindex(x::SUnitRange{Start, L}, i::Int) where {Start, L}
     @boundscheck if i < 1 || i > L
         throw(BoundsError(x, i))
     end
diff --git a/src/StaticArrays.jl b/src/StaticArrays.jl
index d2b7c436..7a0e130d 100644
--- a/src/StaticArrays.jl
+++ b/src/StaticArrays.jl
@@ -1,6 +1,6 @@
 module StaticArrays
 
-import Base: @_propagate_inbounds_meta, @propagate_inbounds, @pure
+import Base: @_propagate_inbounds_meta, @propagate_inbounds
 
 import Base: getindex, setindex!, size, similar, vec, show, length, convert, promote_op,
              promote_rule, map, map!, reduce, mapreduce, foldl, mapfoldl, broadcast,
diff --git a/src/abstractarray.jl b/src/abstractarray.jl
index 84078979..711d1e68 100644
--- a/src/abstractarray.jl
+++ b/src/abstractarray.jl
@@ -1,7 +1,7 @@
 length(a::StaticArrayLike) = prod(Size(a))::Int
 length(a::Type{SA}) where {SA <: StaticArrayLike} = prod(Size(SA))::Int
 
-@pure size(::Type{SA}) where {SA <: StaticArrayLike} = Tuple(Size(SA))
+size(::Type{SA}) where {SA <: StaticArrayLike} = Tuple(Size(SA))
 @inline function size(t::Type{<:StaticArrayLike}, d::Int)
     S = size(t)
     d > length(S) ? 1 : S[d]
@@ -9,7 +9,7 @@ end
 @inline size(a::StaticArrayLike) = Tuple(Size(a))
 
 Base.axes(s::StaticArray) = _axes(Size(s))
-@pure function _axes(::Size{sizes}) where {sizes}
+function _axes(::Size{sizes}) where {sizes}
     map(SOneTo, sizes)
 end
 Base.axes(rv::Adjoint{<:Any,<:StaticVector})   = (SOneTo(1), axes(rv.parent)...)
@@ -86,9 +86,9 @@ sizedarray_similar_type(::Type{T},s::Size{S},::Type{Val{D}}) where {T,S,D} = Siz
 # Utility for computing the eltype of an array instance, type, or type
 # constructor.  For type constructors without a definite eltype, the default
 # value is returned.
-Base.@pure _eltype_or(a::AbstractArray, default) = eltype(a)
-Base.@pure _eltype_or(::Type{<:AbstractArray{T}}, default) where {T} = T
-Base.@pure _eltype_or(::Type{<:AbstractArray}, default) = default # eltype not available
+_eltype_or(a::AbstractArray, default) = eltype(a)
+_eltype_or(::Type{<:AbstractArray{T}}, default) where {T} = T
+_eltype_or(::Type{<:AbstractArray}, default) = default # eltype not available
 
 """
     _construct_similar(a, ::Size, elements::NTuple)
diff --git a/src/convert.jl b/src/convert.jl
index 534a3d4e..814f3ddb 100644
--- a/src/convert.jl
+++ b/src/convert.jl
@@ -10,15 +10,15 @@ Length(x::Args) = Length(length(x.args))
 const BadArgs = Args{<:Tuple{Tuple{<:Tuple}}}
 
 # Some help functions.
-@pure has_ndims(::Type{<:StaticArray{<:Tuple,<:Any,N}}) where {N} = @isdefined N
-@pure has_ndims(::Type{<:StaticArray}) = false
+has_ndims(::Type{<:StaticArray{<:Tuple,<:Any,N}}) where {N} = true
+has_ndims(::Type{<:StaticArray}) = false
 if VERSION < v"1.7"
-    Base.ndims(::Type{<:StaticArray{<:Tuple,<:Any,N}}) where {N} = N
+    Base.ndims(::Type{<:StaticArray{<:Tuple,<:Any,N}}) where {N} = true
 end
-@pure has_eltype(::Type{<:StaticArray{<:Tuple,T}}) where {T} = @isdefined T
-@pure has_eltype(::Type{<:StaticArray}) = false
-@pure has_size(::Type{<:StaticArray{S}}) where {S<:Tuple} = @isdefined S
-@pure has_size(::Type{<:StaticArray}) = false
+has_eltype(::Type{<:StaticArray{<:Tuple,T}}) where {T} = true
+has_eltype(::Type{<:StaticArray}) = false
+has_size(::Type{<:StaticArray{S}}) where {S<:Tuple} = true
+has_size(::Type{<:StaticArray}) = false
 # workaround for https://github.com/JuliaArrays/StaticArrays.jl/issues/1047
 has_size(::Type{SVector}) = false
 has_size(::Type{MVector}) = false
@@ -27,11 +27,11 @@ has_size(::Type{MMatrix}) = false
 has_size(::Type{SMatrix{N}}) where {N} = false
 has_size(::Type{MMatrix{N}}) where {N} = false
 
-@pure has_size1(::Type{<:StaticMatrix{M}}) where {M} = @isdefined M
-@pure has_size1(::Type{<:StaticMatrix}) = false
+has_size1(::Type{<:StaticMatrix{M}}) where {M} = true
+has_size1(::Type{<:StaticMatrix}) = false
 _size1(::Type{<:StaticMatrix{M}}) where {M} = M
 @generated function _sqrt(::Length{L}) where {L}
-    N = round(Int, sqrt(L))
+    N = isqrt(L)
     N^2 == L && return :($N)
     throw(DimensionMismatch("Input's length must be perfect square"))
 end
@@ -40,15 +40,15 @@ end
     SA′ = construct_type(::Type{SA}, x) where {SA<:StaticArray}
 
 Pick a proper constructor `SA′` based on `x` if `SA(x)`/`SA(x...)` has no specific definition.
-The default returned `SA′` is `SA` itself for user defined `StaticArray`s. This differs from 
+The default returned `SA′` is `SA` itself for user defined `StaticArray`s. This differs from
 `similar_type()` in that `SA′` should always be a subtype of `SA`.
 
 !!! note
-    To distinguish `SA(x...)` and `SA(x::Tuple)`, the former calls 
+    To distinguish `SA(x...)` and `SA(x::Tuple)`, the former calls
     `construct_type(SA, StaticArrays.Args(x))` instead of `construct_type(SA, x)`.
 
 !!! note
-    Please make sure `SA'(x)` has a specific definition if the default behavior is overloaded. 
+    Please make sure `SA'(x)` has a specific definition if the default behavior is overloaded.
     Otherwise construction might fall into infinite recursion.
 
 ---
@@ -66,7 +66,7 @@ The adaption rules for offical `StaticArray`s could be summarized as:
 
  If `SA` is not fully static-sized, then we always try to fill `SA` with `x`'s elements,
  and the constructor's `Size` is derived based on:
- 1. If `SA <: StaticVector`, then we use `length(x)` as the output `Length` 
+ 1. If `SA <: StaticVector`, then we use `length(x)` as the output `Length`
  2. If `SA <: StaticMatrix{M}`, then we use `(M, N)` (`N = length(x) ÷ M`) as the output `Size`
  3. If `SA <: StaticMatrix{M,M} where M`, then we use `(N, N)` (`N = sqrt(length(x)`) as the output `Size`.
 - SA(x...)
@@ -215,4 +215,4 @@ end
 
 # `float` and `real` of StaticArray types, analogously to application to scalars (issue 935)
 float(::Type{SA}) where SA<:StaticArray{_S,T,_N} where {_S,T,_N} = similar_type(SA, float(T))
-real(::Type{SA}) where SA<:StaticArray{_S,T,_N} where {_S,T,_N} = similar_type(SA, real(T))
\ No newline at end of file
+real(::Type{SA}) where SA<:StaticArray{_S,T,_N} where {_S,T,_N} = similar_type(SA, real(T))
diff --git a/src/indexing.jl b/src/indexing.jl
index c73bfc0d..3c845940 100644
--- a/src/indexing.jl
+++ b/src/indexing.jl
@@ -71,7 +71,7 @@ end
 ## Indexing utilities  ##
 #########################
 
-@pure unpack_size(::Type{Size{S}}) where {S} = map(Size, S)
+unpack_size(::Type{Size{S}}) where {S} = map(Size, S)
 
 @inline index_size(::Size, ::Int) = Size()
 @inline index_size(::Size, a::StaticArray) = Size(a)
diff --git a/src/initializers.jl b/src/initializers.jl
index edbae358..23e8ca4c 100644
--- a/src/initializers.jl
+++ b/src/initializers.jl
@@ -37,11 +37,9 @@ const SA_F64 = SA{Float64}
 @inline Base.typed_hcat(sa::Type{SA}, xs::Number...)            = similar_type(sa, Size(1,length(xs)))(xs)
 @inline Base.typed_hcat(sa::Type{SA{T}}, xs::Number...) where T = similar_type(sa, Size(1,length(xs)))(xs)
 
-Base.@pure function _SA_hvcat_transposed_size(rows)
+function _SA_hvcat_transposed_size(rows)
     M = rows[1]
     if any(r->r != M, rows)
-        # @pure may not throw... probably. See
-        # https://discourse.julialang.org/t/can-pure-functions-throw-an-error/18459
         return nothing
     end
     Size(M, length(rows))
@@ -65,7 +63,7 @@ if VERSION >= v"1.7"
     args = (:(x[$i]) for i in a)
     return :(tuple($(args...)))
 end
-    
+
 @inline function _SA_typed_hvncat(sa, dimsshape, row_first, xs)
     msize = Size(dimsshape)
     xs′ = row_first ? reorder(xs, Val(msize[1]), Val(msize[2])) : xs
diff --git a/src/traits.jl b/src/traits.jl
index 94054140..14118b9b 100644
--- a/src/traits.jl
+++ b/src/traits.jl
@@ -33,34 +33,32 @@ Base.show(io::IO, ::Length{L}) where {L} = print(io, "Length(", L, ")")
 
 Length(a::AbstractArray) = Length(Size(a))
 Length(::Type{A}) where {A <: AbstractArray} = Length(Size(A))
-@pure Length(L::Int) = Length{L}()
+Length(L::Int) = Length{L}()
 Length(::Size{S}) where {S} = _Length(S...)
-@pure _Length(S::Int...) = Length{prod(S)}()
+_Length(S::Int...) = Length{prod(S)}()
 @inline _Length(S...) = Length{Dynamic()}()
 
-# Some @pure convenience functions for `Size`
-@pure (::Type{Tuple})(::Size{S}) where {S} = S
+(::Type{Tuple})(::Size{S}) where {S} = S
 
-@pure getindex(::Size{S}, i::Int) where {S} = i <= length(S) ? S[i] : 1
+getindex(::Size{S}, i::Int) where {S} = i <= length(S) ? S[i] : 1
 
-@pure length(::Size{S}) where {S} = length(S)
-@pure length_val(::Size{S}) where {S} = Val{length(S)}
+length(::Size{S}) where {S} = length(S)
+length_val(::Size{S}) where {S} = Val{length(S)}
 
 # Note - using === here, as Base doesn't inline == for tuples as of julia-0.6
-@pure Base.:(==)(::Size{S}, s::Tuple{Vararg{Int}}) where {S} = S === s
-@pure Base.:(==)(s::Tuple{Vararg{Int}}, ::Size{S}) where {S} = s === S
+Base.:(==)(::Size{S}, s::Tuple{Vararg{Int}}) where {S} = S === s
+Base.:(==)(s::Tuple{Vararg{Int}}, ::Size{S}) where {S} = s === S
 
-@pure Base.prod(::Size{S}) where {S} = prod(S)
+Base.prod(::Size{S}) where {S} = prod(S)
 
 Base.LinearIndices(::Size{S}) where {S} = LinearIndices(S)
 
-@pure size_tuple(::Size{S}) where {S} = Tuple{S...}
+size_tuple(::Size{S}) where {S} = Tuple{S...}
 
-# Some @pure convenience functions for `Length`
-@pure (::Type{Int})(::Length{L}) where {L} = L
+(::Type{Int})(::Length{L}) where {L} = L
 
-@pure Base.:(==)(::Length{L}, l::Int) where {L} = L == l
-@pure Base.:(==)(l::Int, ::Length{L}) where {L} = l == L
+Base.:(==)(::Length{L}, l::Int) where {L} = L == l
+Base.:(==)(l::Int, ::Length{L}) where {L} = l == L
 
 # unroll_tuple also works with `Length`
 @propagate_inbounds unroll_tuple(f, ::Length{L}) where {L} = unroll_tuple(f, Val{L})
@@ -72,7 +70,7 @@ Base.LinearIndices(::Size{S}) where {S} = LinearIndices(S)
 Determine whether two sizes match, in the sense that they have the same
 number of dimensions, and their dimensions match as determined by [`dimmatch`](@ref).
 """
-@pure sizematch(::Size{S1}, ::Size{S2}) where {S1, S2} = sizematch(S1, S2)
+sizematch(::Size{S1}, ::Size{S2}) where {S1, S2} = sizematch(S1, S2)
 @inline sizematch(::Tuple{}, ::Tuple{}) = true
 @inline sizematch(S1::Tuple{Vararg{StaticDimension, N}}, S2::Tuple{Vararg{StaticDimension, N}}) where {N} =
     dimmatch(S1[1], S2[1]) && sizematch(Base.tail(S1), Base.tail(S2))
@@ -115,4 +113,4 @@ end
 
 # Return the "diagonal size" of a matrix - the minimum of the two dimensions
 diagsize(A::StaticMatrix) = diagsize(Size(A))
-@pure diagsize(::Size{S}) where {S} = min(S...)
+diagsize(::Size{S}) where {S} = min(S...)