diff --git a/llvm/docs/ReleaseNotes.rst b/llvm/docs/ReleaseNotes.rst
--- a/llvm/docs/ReleaseNotes.rst
+++ b/llvm/docs/ReleaseNotes.rst
@@ -179,6 +179,7 @@
 
 Changes to the LLVM tools
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+* llvm-lib now supports the /def option for generating a Windows import library from a definition file.
 
 Changes to LLDB
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