diff --git a/common.mk b/common.mk
index 81fa5b8f5c..e975d60b4d 100644
--- a/common.mk
+++ b/common.mk
@@ -15302,7 +15302,6 @@ ruby.$(OBJEXT): $(top_srcdir)/prism/pack.h
 ruby.$(OBJEXT): $(top_srcdir)/prism/parser.h
 ruby.$(OBJEXT): $(top_srcdir)/prism/prism.h
 ruby.$(OBJEXT): $(top_srcdir)/prism/regexp.h
-ruby.$(OBJEXT): $(top_srcdir)/prism/unescape.h
 ruby.$(OBJEXT): $(top_srcdir)/prism/util/pm_buffer.h
 ruby.$(OBJEXT): $(top_srcdir)/prism/util/pm_char.h
 ruby.$(OBJEXT): $(top_srcdir)/prism/util/pm_constant_pool.h