diff --git a/.git-blame-ignore-revs b/.git-blame-ignore-revs
index 86be15b72fb6..9ef0713ef8af 100644
--- a/.git-blame-ignore-revs
+++ b/.git-blame-ignore-revs
@@ -94,3 +94,6 @@ b6262880b34629e9d7a72b5a42f315a3c9ed8139
 39c7dc7207e76e72da21cf4fedda21b5311bf62d
 e80bc777749331e9519575f416c342f7626dd14d
 7e5cd8f1b6c5263ed5e2cc03d60c8779a8d3e9f7
+
+# NFC: clang-format test_demangle.pass.cpp but keep test "lines"
+d33bf2e9df578ff7e44fd22504d6ad5a122b7ee6