diff --git a/llvm/include/llvm/FuzzMutate/FuzzerCLI.h b/llvm/include/llvm/FuzzMutate/FuzzerCLI.h
index 2a16e43a6ab3d0..27eec058b59992 100644
--- a/llvm/include/llvm/FuzzMutate/FuzzerCLI.h
+++ b/llvm/include/llvm/FuzzMutate/FuzzerCLI.h
@@ -14,12 +14,13 @@
 #ifndef LLVM_FUZZMUTATE_FUZZER_CLI_H
 #define LLVM_FUZZMUTATE_FUZZER_CLI_H
 
-#include "llvm/ADT/StringRef.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/Support/DataTypes.h"
 
 namespace llvm {
 
+class StringRef;
+
 /// Parse cl::opts from a fuzz target commandline.
 ///
 /// This handles all arguments after -ignore_remaining_args=1 as cl::opts.
diff --git a/llvm/lib/FuzzMutate/FuzzerCLI.cpp b/llvm/lib/FuzzMutate/FuzzerCLI.cpp
index b77a0e0918406b..32eba275da7b9f 100644
--- a/llvm/lib/FuzzMutate/FuzzerCLI.cpp
+++ b/llvm/lib/FuzzMutate/FuzzerCLI.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/FuzzMutate/FuzzerCLI.h"
+#include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/Bitcode/BitcodeReader.h"
 #include "llvm/Bitcode/BitcodeWriter.h"