2 files changed, 3 insertions, 2 deletions

diff --git a/xtask/Cargo.toml b/xtask/Cargo.toml
index 7a2937f0e..61a944c13 100644
--- a/xtask/Cargo.toml
+++ b/xtask/Cargo.toml
@@ -15,7 +15,7 @@ flate2 = "1.0"
 pico-args = "0.3.1"
 proc-macro2 = "1.0.8"
 quote = "1.0.2"
-ungrammar = "1.6"
+ungrammar = "1.7"
 walkdir = "2.3.1"
 write-json = "0.1.0"
 xshell = "0.1"
diff --git a/xtask/src/ast_src.rs b/xtask/src/ast_src.rs
index 2b8012bdd..046d68f52 100644
--- a/xtask/src/ast_src.rs
+++ b/xtask/src/ast_src.rs
@@ -68,7 +68,7 @@ pub(crate) const KINDS_SRC: KindsSrc = KindsSrc {
         "as", "async", "await", "box", "break", "const", "continue", "crate", "dyn", "else",
         "enum", "extern", "false", "fn", "for", "if", "impl", "in", "let", "loop", "macro",
         "match", "mod", "move", "mut", "pub", "ref", "return", "self", "static", "struct", "super",
-        "trait", "true", "try", "type", "unsafe", "use", "where", "while",
+        "trait", "true", "try", "type", "unsafe", "use", "where", "while", "yield",
     ],
     contextual_keywords: &["auto", "default", "existential", "union", "raw", "macro_rules"],
     literals: &["INT_NUMBER", "FLOAT_NUMBER", "CHAR", "BYTE", "STRING", "BYTE_STRING"],
@@ -149,6 +149,7 @@ pub(crate) const KINDS_SRC: KindsSrc = KindsSrc {
         "LABEL",
         "BLOCK_EXPR",
         "RETURN_EXPR",
+        "YIELD_EXPR",
         "MATCH_EXPR",
         "MATCH_ARM_LIST",
         "MATCH_ARM",