diff --git a/.github/workflows/CI.yml b/.github/workflows/CI.yml
index dcdb5f35..b6ceedb5 100644
--- a/.github/workflows/CI.yml
+++ b/.github/workflows/CI.yml
@@ -92,7 +92,7 @@ jobs:
         with:
           version: 1.6
           arch: x64
-      - uses: actions/cache@v1
+      - uses: actions/cache@v4
         env:
           cache-name: cache-artifacts
         with:
diff --git a/src/kinds.jl b/src/kinds.jl
index c7d27e35..b6f0723a 100644
--- a/src/kinds.jl
+++ b/src/kinds.jl
@@ -102,6 +102,12 @@ function _register_kinds!(kind_modules, int_to_kindstr, kind_str_to_int, mod, mo
             error("Kind module ID $module_id already claimed by module $m")
         end
     end
+    _register_kinds_names!(int_to_kindstr, kind_str_to_int, module_id, names)
+end
+
+# This function is separated from `_register_kinds!` to prevent sharing of the variable `i`
+# here and in the closure in `_register_kinds!`, which causes boxing and bad inference.
+function _register_kinds_names!(int_to_kindstr, kind_str_to_int, module_id, names)
     # Process names to conflate category BEGIN/END markers with the first/last
     # in the category.
     i = 0
diff --git a/src/precompile.jl b/src/precompile.jl
index 922be354..5a80d92d 100644
--- a/src/precompile.jl
+++ b/src/precompile.jl
@@ -6,6 +6,7 @@ let filename = joinpath(@__DIR__, "literal_parsing.jl")
     if _has_v1_6_hooks
         enable_in_core!()
         Meta.parse("1 + 2")
+        Meta.parse(SubString("1 + 2"))
         enable_in_core!(false)
     end
 end
diff --git a/src/tokenize.jl b/src/tokenize.jl
index 6eb76954..0ea9be19 100644
--- a/src/tokenize.jl
+++ b/src/tokenize.jl
@@ -1339,7 +1339,8 @@ end
 function simple_hash(str)
     ind = 1
     h = UInt64(0)
-    while ind <= length(str)
+    L = min(lastindex(str), MAX_KW_LENGTH)
+    while ind <= L
         h = simple_hash(str[ind], h)
         ind = nextind(str, ind)
     end