Index: clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp
===================================================================
--- clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp
+++ clang-tools-extra/clang-tidy/ClangTidyDiagnosticConsumer.cpp
@@ -757,9 +757,12 @@
 std::vector<ClangTidyError> ClangTidyDiagnosticConsumer::take() {
   finalizeLastError();
 
-  std::sort(Errors.begin(), Errors.end(), LessClangTidyError());
-  Errors.erase(std::unique(Errors.begin(), Errors.end(), EqualClangTidyError()),
-               Errors.end());
+  if (!*Context.getOptions().DuplicateReports) {
+    std::sort(Errors.begin(), Errors.end(), LessClangTidyError());
+    Errors.erase(std::unique(Errors.begin(), Errors.end(),
+                 EqualClangTidyError()), Errors.end());
+  }
+
   if (RemoveIncompatibleErrors)
     removeIncompatibleErrors();
   return std::move(Errors);
Index: clang-tools-extra/clang-tidy/ClangTidyOptions.h
===================================================================
--- clang-tools-extra/clang-tidy/ClangTidyOptions.h
+++ clang-tools-extra/clang-tidy/ClangTidyOptions.h
@@ -66,6 +66,10 @@
   /// \brief WarningsAsErrors filter.
   llvm::Optional<std::string> WarningsAsErrors;
 
+  /// \brief Indicates whether warnings emitted by alias checkers should be
+  /// reported multiple times.
+  llvm::Optional<bool> DuplicateReports;
+
   /// \brief Output warnings from headers matching this filter. Warnings from
   /// main files will always be displayed.
   llvm::Optional<std::string> HeaderFilterRegex;
Index: clang-tools-extra/clang-tidy/ClangTidyOptions.cpp
===================================================================
--- clang-tools-extra/clang-tidy/ClangTidyOptions.cpp
+++ clang-tools-extra/clang-tidy/ClangTidyOptions.cpp
@@ -105,6 +105,7 @@
   ClangTidyOptions Options;
   Options.Checks = "";
   Options.WarningsAsErrors = "";
+  Options.DuplicateReports = false;
   Options.HeaderFilterRegex = "";
   Options.SystemHeaders = false;
   Options.FormatStyle = "none";
@@ -145,6 +146,7 @@
   mergeCommaSeparatedLists(Result.Checks, Other.Checks);
   mergeCommaSeparatedLists(Result.WarningsAsErrors, Other.WarningsAsErrors);
   overrideValue(Result.HeaderFilterRegex, Other.HeaderFilterRegex);
+  overrideValue(Result.DuplicateReports, Other.DuplicateReports);
   overrideValue(Result.SystemHeaders, Other.SystemHeaders);
   overrideValue(Result.FormatStyle, Other.FormatStyle);
   overrideValue(Result.User, Other.User);
Index: clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp
===================================================================
--- clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp
+++ clang-tools-extra/clang-tidy/tool/ClangTidyMain.cpp
@@ -78,6 +78,15 @@
                                              cl::init(""),
                                              cl::cat(ClangTidyCategory));
 
+static cl::opt<bool> DuplicateReports("duplicate-reports", cl::desc(R"(
+Some checkers are aliases of others, so the same
+issue may be reported by different checkers at
+the same location. These duplicates are uniqued
+unless this flag is provided.
+)"),
+                                             cl::init(false),
+                                             cl::cat(ClangTidyCategory));
+
 static cl::opt<std::string> HeaderFilter("header-filter", cl::desc(R"(
 Regular expression matching the names of the
 headers to output diagnostics from. Diagnostics
@@ -266,6 +275,7 @@
   ClangTidyOptions DefaultOptions;
   DefaultOptions.Checks = DefaultChecks;
   DefaultOptions.WarningsAsErrors = "";
+  DefaultOptions.DuplicateReports = DuplicateReports;
   DefaultOptions.HeaderFilterRegex = HeaderFilter;
   DefaultOptions.SystemHeaders = SystemHeaders;
   DefaultOptions.FormatStyle = FormatStyle;
@@ -279,6 +289,8 @@
     OverrideOptions.Checks = Checks;
   if (WarningsAsErrors.getNumOccurrences() > 0)
     OverrideOptions.WarningsAsErrors = WarningsAsErrors;
+  if (DuplicateReports.getNumOccurrences() > 0)
+    OverrideOptions.DuplicateReports = DuplicateReports;
   if (HeaderFilter.getNumOccurrences() > 0)
     OverrideOptions.HeaderFilterRegex = HeaderFilter;
   if (SystemHeaders.getNumOccurrences() > 0)
Index: clang-tools-extra/test/clang-tidy/duplicate-reports-with.cpp
===================================================================
--- /dev/null
+++ clang-tools-extra/test/clang-tidy/duplicate-reports-with.cpp
@@ -0,0 +1,19 @@
+// RUN: %check_clang_tidy %s cert-err09-cpp,cert-err61-cpp %t -duplicate-reports --
+
+void alwaysThrows() {
+  int ex = 42;
+  // At this location both cert-err09-cpp and cert-err61-cpp report the
+  // message. The order of the reports is unknown, that's why the checker name
+  // is not included in the expected warning.
+
+  // CHECK-MESSAGES: warning: throw expression should throw anonymous temporary values instead
+  // CHECK-MESSAGES: warning: throw expression should throw anonymous temporary values instead
+  throw ex;
+}
+
+void doTheJob() {
+  try {
+    alwaysThrows();
+  } catch (int&) {
+  }
+}
Index: clang-tools-extra/test/clang-tidy/duplicate-reports-without.cpp
===================================================================
--- /dev/null
+++ clang-tools-extra/test/clang-tidy/duplicate-reports-without.cpp
@@ -0,0 +1,17 @@
+// RUN: %check_clang_tidy %s cert-err09-cpp,cert-err61-cpp %t
+
+void alwaysThrows() {
+  int ex = 42;
+  // It is unknown which checker alias is reporting the warning, that is why
+  // the checker name is not included in the message.
+
+  // CHECK-MESSAGES: warning: throw expression should throw anonymous temporary values instead
+  throw ex;
+}
+
+void doTheJob() {
+  try {
+    alwaysThrows();
+  } catch (int&) {
+  }
+}