Fix bug

Author: penelopeysm

src/fasteval.jl

@@ -364,7 +364,9 @@ function fast_evaluate!!(model::Model, ctx::FastEvalVectorContext, accs::Accumul
     # https://github.com/TuringLang/DynamicPPL.jl/issues/1086
     vi = if Threads.nthreads() > 1
         accs = map(
-            acc -> DynamicPPL.convert_eltype(float_type_with_fallback(eltype(params)), acc),
+            acc -> DynamicPPL.convert_eltype(
+                float_type_with_fallback(eltype(ctx.params)), acc
+            ),
             accs,
         )
         ThreadSafeVarInfo(OnlyAccsVarInfo(accs))