Index: clang/include/clang/Analysis/IssueHash.h
===================================================================
--- clang/include/clang/Analysis/IssueHash.h
+++ clang/include/clang/Analysis/IssueHash.h
@@ -12,7 +12,6 @@
 
 namespace clang {
 class Decl;
-class SourceManager;
 class FullSourceLoc;
 class LangOptions;
 
@@ -25,26 +24,31 @@
 /// The hash contains the normalized text of the location associated with the
 /// diagnostic. Normalization means removing the whitespaces. The associated
 /// location is the either the last location of a diagnostic path or a uniqueing
-/// location. The bugtype and the name of the checker is also part of the hash.
+/// location. The warning message and the name of the checker (the entity that
+/// was responsible for displaying the issue) is also part of the hash.
 /// The last component is the string representation of the enclosing declaration
 /// of the associated location.
 ///
+/// If the warning message is flaky (e.g. contains line numbers), it makes sense
+/// to put a simplified message text into the hash.
+///
 /// In case a new hash is introduced, the old one should still be maintained for
 /// a while. One should not introduce a new hash for every change, it is
 /// possible to introduce experimental hashes that may change in the future.
 /// Such hashes should be marked as experimental using a comment in the plist
 /// files.
-llvm::SmallString<32> GetIssueHash(const SourceManager &SM,
-                                   FullSourceLoc &IssueLoc,
-                                   llvm::StringRef CheckerName,
-                                   llvm::StringRef BugType, const Decl *D,
-                                   const LangOptions &LangOpts);
+llvm::SmallString<32>
+GetIssueHash(FullSourceLoc &IssueLoc,
+             llvm::StringRef CheckerName, llvm::StringRef WarningMessage,
+             const Decl *IssueDecl, const LangOptions &LangOpts);
 
 /// Get the string representation of issue hash. See GetIssueHash() for
 /// more information.
-std::string GetIssueString(const SourceManager &SM, FullSourceLoc &IssueLoc,
-                           llvm::StringRef CheckerName, llvm::StringRef BugType,
-                           const Decl *D, const LangOptions &LangOpts);
+std::string GetIssueString(FullSourceLoc &IssueLoc,
+                           llvm::StringRef CheckerName,
+                           llvm::StringRef WarningMessage,
+                           const Decl *IssueDecl,
+                           const LangOptions &LangOpts);
 } // namespace clang
 
 #endif
Index: clang/lib/Analysis/CMakeLists.txt
===================================================================
--- clang/lib/Analysis/CMakeLists.txt
+++ clang/lib/Analysis/CMakeLists.txt
@@ -16,6 +16,7 @@
   CodeInjector.cpp
   Dominators.cpp
   ExprMutationAnalyzer.cpp
+  IssueHash.cpp
   LiveVariables.cpp
   ObjCNoReturn.cpp
   PathDiagnostic.cpp
Index: clang/lib/Analysis/IssueHash.cpp
===================================================================
--- clang/lib/Analysis/IssueHash.cpp
+++ clang/lib/Analysis/IssueHash.cpp
@@ -5,7 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-#include "clang/StaticAnalyzer/Core/IssueHash.h"
+
+#include "clang/Analysis/IssueHash.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/DeclCXX.h"
@@ -179,26 +180,27 @@
   return Res;
 }
 
-std::string clang::GetIssueString(const SourceManager &SM,
-                                  FullSourceLoc &IssueLoc,
-                                  StringRef CheckerName, StringRef BugType,
-                                  const Decl *D,
+std::string clang::GetIssueString(FullSourceLoc &IssueLoc,
+                                  StringRef CheckerName,
+                                  StringRef WarningMessage,
+                                  const Decl *IssueDecl,
                                   const LangOptions &LangOpts) {
   static StringRef Delimiter = "$";
 
   return (llvm::Twine(CheckerName) + Delimiter +
-          GetEnclosingDeclContextSignature(D) + Delimiter +
+          GetEnclosingDeclContextSignature(IssueDecl) + Delimiter +
           Twine(IssueLoc.getExpansionColumnNumber()) + Delimiter +
-          NormalizeLine(SM, IssueLoc, LangOpts) + Delimiter + BugType)
+          NormalizeLine(IssueLoc.getManager(), IssueLoc, LangOpts) +
+          Delimiter + WarningMessage)
       .str();
 }
 
-SmallString<32> clang::GetIssueHash(const SourceManager &SM,
-                                    FullSourceLoc &IssueLoc,
-                                    StringRef CheckerName, StringRef BugType,
-                                    const Decl *D,
+SmallString<32> clang::GetIssueHash(FullSourceLoc &IssueLoc,
+                                    StringRef CheckerName,
+                                    StringRef WarningMessage,
+                                    const Decl *IssueDecl,
                                     const LangOptions &LangOpts) {
 
-  return GetHashOfContent(
-      GetIssueString(SM, IssueLoc, CheckerName, BugType, D, LangOpts));
+  return GetHashOfContent(GetIssueString(IssueLoc, CheckerName, WarningMessage,
+                                         IssueDecl, LangOpts));
 }
Index: clang/lib/StaticAnalyzer/Checkers/ExprInspectionChecker.cpp
===================================================================
--- clang/lib/StaticAnalyzer/Checkers/ExprInspectionChecker.cpp
+++ clang/lib/StaticAnalyzer/Checkers/ExprInspectionChecker.cpp
@@ -6,11 +6,11 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "clang/Analysis/IssueHash.h"
 #include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
 #include "clang/StaticAnalyzer/Checkers/SValExplainer.h"
 #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
 #include "clang/StaticAnalyzer/Core/Checker.h"
-#include "clang/StaticAnalyzer/Core/IssueHash.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
 #include "llvm/ADT/StringSwitch.h"
@@ -305,7 +305,7 @@
   const SourceManager &SM = C.getSourceManager();
   FullSourceLoc FL(CE->getArg(0)->getBeginLoc(), SM);
   std::string HashContent =
-      GetIssueString(SM, FL, getCheckName().getName(), "Category",
+      GetIssueString(FL, getCheckName().getName(), "Category",
                      C.getLocationContext()->getDecl(), Opts);
 
   reportBug(HashContent, C);
Index: clang/lib/StaticAnalyzer/Core/CMakeLists.txt
===================================================================
--- clang/lib/StaticAnalyzer/Core/CMakeLists.txt
+++ clang/lib/StaticAnalyzer/Core/CMakeLists.txt
@@ -26,7 +26,6 @@
   ExprEngineObjC.cpp
   FunctionSummary.cpp
   HTMLDiagnostics.cpp
-  IssueHash.cpp
   LoopUnrolling.cpp
   LoopWidening.cpp
   MemRegion.cpp
Index: clang/lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp
===================================================================
--- clang/lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp
+++ clang/lib/StaticAnalyzer/Core/HTMLDiagnostics.cpp
@@ -10,6 +10,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "clang/Analysis/IssueHash.h"
 #include "clang/Analysis/PathDiagnostic.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/DeclBase.h"
@@ -23,7 +24,6 @@
 #include "clang/Lex/Token.h"
 #include "clang/Rewrite/Core/HTMLRewrite.h"
 #include "clang/Rewrite/Core/Rewriter.h"
-#include "clang/StaticAnalyzer/Core/IssueHash.h"
 #include "clang/StaticAnalyzer/Core/PathDiagnosticConsumers.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/SmallString.h"
@@ -554,7 +554,7 @@
     os  << "\n<!-- FUNCTIONNAME " <<  declName << " -->\n";
 
     os << "\n<!-- ISSUEHASHCONTENTOFLINEINCONTEXT "
-       << GetIssueHash(SMgr, L, D.getCheckName(), D.getBugType(), DeclWithIssue,
+       << GetIssueHash(L, D.getCheckName(), D.getBugType(), DeclWithIssue,
                        PP.getLangOpts()) << " -->\n";
 
     os << "\n<!-- BUGLINE "
Index: clang/lib/StaticAnalyzer/Core/PlistDiagnostics.cpp
===================================================================
--- clang/lib/StaticAnalyzer/Core/PlistDiagnostics.cpp
+++ clang/lib/StaticAnalyzer/Core/PlistDiagnostics.cpp
@@ -10,6 +10,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "clang/Analysis/IssueHash.h"
 #include "clang/Analysis/PathDiagnostic.h"
 #include "clang/Basic/FileManager.h"
 #include "clang/Basic/PlistSupport.h"
@@ -20,7 +21,6 @@
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Lex/TokenConcatenation.h"
 #include "clang/Rewrite/Core/HTMLRewrite.h"
-#include "clang/StaticAnalyzer/Core/IssueHash.h"
 #include "clang/StaticAnalyzer/Core/PathDiagnosticConsumers.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
@@ -680,9 +680,8 @@
                                             : D->getLocation().asLocation()),
                     SM);
     const Decl *DeclWithIssue = D->getDeclWithIssue();
-    EmitString(o, GetIssueHash(SM, L, D->getCheckName(), D->getBugType(),
-                               DeclWithIssue, LangOpts))
-        << '\n';
+    EmitString(o, GetIssueHash(L, D->getCheckName(), D->getBugType(),
+                               DeclWithIssue, LangOpts)) << '\n';
 
     // Output information about the semantic context where
     // the issue occurred.