diff --git a/llvm/tools/llvm-exegesis/lib/CMakeLists.txt b/llvm/tools/llvm-exegesis/lib/CMakeLists.txt
--- a/llvm/tools/llvm-exegesis/lib/CMakeLists.txt
+++ b/llvm/tools/llvm-exegesis/lib/CMakeLists.txt
@@ -27,6 +27,7 @@
   BenchmarkRunner.cpp
   Clustering.cpp
   CodeTemplate.cpp
+  Error.cpp
   LatencyBenchmarkRunner.cpp
   LlvmState.cpp
   MCInstrDescView.cpp
diff --git a/llvm/tools/llvm-exegesis/lib/Clustering.cpp b/llvm/tools/llvm-exegesis/lib/Clustering.cpp
--- a/llvm/tools/llvm-exegesis/lib/Clustering.cpp
+++ b/llvm/tools/llvm-exegesis/lib/Clustering.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "Clustering.h"
+#include "Error.h"
 #include "llvm/ADT/SetVector.h"
 #include "llvm/ADT/SmallSet.h"
 #include "llvm/ADT/SmallVector.h"
@@ -106,14 +107,13 @@
     const auto *CurMeasurement = &Point.Measurements;
     if (LastMeasurement) {
       if (LastMeasurement->size() != CurMeasurement->size()) {
-        return make_error<StringError>("inconsistent measurement dimensions",
-                                       inconvertibleErrorCode());
+        return make_error<ClusteringError>(
+            "inconsistent measurement dimensions");
       }
       for (size_t I = 0, E = LastMeasurement->size(); I < E; ++I) {
         if (LastMeasurement->at(I).Key != CurMeasurement->at(I).Key) {
-          return make_error<StringError>(
-              "inconsistent measurement dimensions keys",
-              inconvertibleErrorCode());
+          return make_error<ClusteringError>(
+              "inconsistent measurement dimensions keys");
         }
       }
     }
@@ -333,7 +333,7 @@
       Clustering.stabilize(NumOpcodes.getValue());
   } else /*if(Mode == ModeE::Naive)*/ {
     if (!NumOpcodes.hasValue())
-      report_fatal_error(
+      return make_error<Failure>(
           "'naive' clustering mode requires opcode count to be specified");
     Clustering.clusterizeNaive(NumOpcodes.getValue());
   }
diff --git a/llvm/tools/llvm-exegesis/lib/Error.h b/llvm/tools/llvm-exegesis/lib/Error.h
--- a/llvm/tools/llvm-exegesis/lib/Error.h
+++ b/llvm/tools/llvm-exegesis/lib/Error.h
@@ -22,6 +22,19 @@
   Failure(const Twine &S) : StringError(S, inconvertibleErrorCode()) {}
 };
 
+// A class representing failures that happened during clustering calculations.
+class ClusteringError : public ErrorInfo<ClusteringError> {
+public:
+  static char ID;
+  ClusteringError(const Twine&S) : Msg(S.str()) {}
+
+  void log(raw_ostream &OS) const override;
+
+  std::error_code convertToErrorCode() const override;
+private:
+    std::string Msg;
+};
+
 } // namespace exegesis
 } // namespace llvm
 
diff --git a/llvm/tools/llvm-exegesis/lib/Error.cpp b/llvm/tools/llvm-exegesis/lib/Error.cpp
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-exegesis/lib/Error.cpp
@@ -0,0 +1,25 @@
+//===-- Error.cpp -----------------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "Error.h"
+
+namespace llvm {
+namespace exegesis {
+
+char ClusteringError::ID;
+
+void ClusteringError::log(raw_ostream &OS) const {
+  OS << Msg;
+}
+
+std::error_code ClusteringError::convertToErrorCode() const {
+  return inconvertibleErrorCode();
+}
+
+} // namespace exegesis
+} // namespace llvm
diff --git a/llvm/tools/llvm-exegesis/llvm-exegesis.cpp b/llvm/tools/llvm-exegesis/llvm-exegesis.cpp
--- a/llvm/tools/llvm-exegesis/llvm-exegesis.cpp
+++ b/llvm/tools/llvm-exegesis/llvm-exegesis.cpp
@@ -373,7 +373,7 @@
   cl::ParseCommandLineOptions(Argc, Argv, "");
 
   exegesis::ExitOnErr.setExitCodeMapper([](const Error &Err) {
-    if (Err.isA<StringError>())
+    if (Err.isA<exegesis::ClusteringError>())
       return EXIT_SUCCESS;
     return EXIT_FAILURE;
   });