diff --git a/Project.toml b/Project.toml
index 7e22dd203..7b7283b96 100644
--- a/Project.toml
+++ b/Project.toml
@@ -34,7 +34,7 @@ SparseArraysExt = "SparseArrays"
 Adapt = "0.4, 1.0, 2.0, 3.0, 4"
 Atomix = "0.1, 1"
 EnzymeCore = "0.7, 0.8.1"
-GPUCompiler = "1.6"
+GPUCompiler = "1.13.3"
 InteractiveUtils = "1.6"
 LLVM = "9.4.1"
 LinearAlgebra = "1.6"
diff --git a/src/nditeration.jl b/src/nditeration.jl
index 24ff094cf..3b2be2353 100644
--- a/src/nditeration.jl
+++ b/src/nditeration.jl
@@ -118,6 +118,10 @@ Base.@propagate_inbounds function expand(ndrange::NDRange, groupidx::Integer, id
     W = workitems(ndrange)
     assume_nonzero(B)
     assume_nonzero(W)
+    assume(groupidx >= 1)
+    assume(groupidx <= length(B))
+    assume(idx >= 1)
+    assume(idx <= length(W))
     return expand(ndrange, B[groupidx], workitems(ndrange)[idx])
 end