diff --git a/tools/warn/other_warn_patterns.py b/tools/warn/other_warn_patterns.py
index 318c3d4..8df5b87 100644
--- a/tools/warn/other_warn_patterns.py
+++ b/tools/warn/other_warn_patterns.py
@@ -143,6 +143,8 @@
     # Yacc warnings
     yacc('deprecate directive',
          [r".*\.yy?:.*: warning: deprecated directive: "]),
+    yacc('reduce/reduce conflicts',
+         [r".*\.yy?: warning: .+ reduce/reduce conflicts "]),
     yacc('shift/reduce conflicts',
          [r".*\.yy?: warning: .+ shift/reduce conflicts "]),
     {'category': 'yacc', 'severity': Severity.SKIP,