diff --git a/macro/Cargo.toml b/macro/Cargo.toml
index 5819d3d862..7e8650c498 100644
--- a/macro/Cargo.toml
+++ b/macro/Cargo.toml
@@ -20,9 +20,8 @@ proc-macro2 = "1"
 quote = "1"
 regex = "1.10.6"
 syn = { version = "2", features = ["full"] }
-tblgen = { version = "0.3.6", features = [
-  # TODO Use a `llvm19-0` flag.
-  "llvm18-0",
+tblgen = { version = "0.4.0", features = [
+  "llvm19-0",
 ], default-features = false, package = "tblgen-alt" }
 unindent = "0.2.3"