Index: lib/StaticAnalyzer/Core/PlistDiagnostics.cpp
===================================================================
--- lib/StaticAnalyzer/Core/PlistDiagnostics.cpp
+++ lib/StaticAnalyzer/Core/PlistDiagnostics.cpp
@@ -22,6 +22,11 @@
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Support/Casting.h"
+#include "llvm/Support/LineIterator.h"
+#include "clang/AST/ASTContext.h"
+#include "llvm/Support/MD5.h"
+#include <sstream>
+
 using namespace clang;
 using namespace ento;
 using namespace markup;
@@ -285,6 +290,57 @@
   }
 }
 
+static std::string GetNthLineOfFile(llvm::MemoryBuffer *Buffer, int Line) {
+  if (!Buffer)
+    return "";
+
+  llvm::line_iterator LI(*Buffer, false);
+  for (; !LI.is_at_eof() && LI.line_number() != Line; ++LI)
+    ;
+
+  return LI->str();
+}
+
+static std::string NormalizeLine(const SourceManager *SM, FullSourceLoc &L,
+                                 const Decl *D) {
+  static const std::string whitespaces = " \t\n";
+
+  const LangOptions &Opts = D->getASTContext().getLangOpts();
+  std::string str = GetNthLineOfFile(SM->getBuffer(L.getFileID(), L), L.getExpansionLineNumber());
+  unsigned col = str.find_first_not_of(whitespaces);
+
+  SourceLocation StartOfLine = SM->translateLineCol(SM->getFileID(L), L.getExpansionLineNumber(), col);
+  llvm::MemoryBuffer *Buffer = SM->getBuffer(SM->getFileID(StartOfLine), StartOfLine);
+  if (!Buffer) return {};
+
+  const char *BufferPos = SM->getCharacterData(StartOfLine);
+
+  Token Token;
+  Lexer Lexer(SM->getLocForStartOfFile(SM->getFileID(StartOfLine)), Opts,
+              Buffer->getBufferStart(), BufferPos, Buffer->getBufferEnd());
+
+  size_t nextStart = 0;
+  std::ostringstream lineBuff;
+  while (!Lexer.LexFromRawLexer(Token) && nextStart < 2) {
+    if (Token.isAtStartOfLine() && nextStart++ > 0) continue;
+    lineBuff << std::string(SM->getCharacterData(Token.getLocation()), Token.getLength());
+  }
+
+  return lineBuff.str();
+}
+
+static llvm::SmallString<32> GetHashOfContent(StringRef Content) {
+  llvm::MD5 Hash;
+  llvm::MD5::MD5Result MD5Res;
+  llvm::SmallString<32> Res;
+
+  Hash.update(Content);
+  Hash.final(MD5Res);
+  llvm::MD5::stringifyResult(MD5Res, Res);
+
+  return Res;
+}
+
 void PlistDiagnostics::FlushDiagnosticsImpl(
                                     std::vector<const PathDiagnostic *> &Diags,
                                     FilesMade *filesMade) {
@@ -420,9 +476,12 @@
           EmitString(o, declName) << '\n';
         }
 
-        // Output the bug hash for issue unique-ing. Currently, it's just an
-        // offset from the beginning of the function.
-        if (const Stmt *Body = DeclWithIssue->getBody()) {
+        // Output the bug hash for issue unique-ing.
+        // Currently, it contains the following information:
+        //   1. column number
+        //   2. source line string after removing whitespace
+        //   3. bug type
+        if (DeclWithIssue->getBody()) {
 
           // If the bug uniqueing location exists, use it for the hash.
           // For example, this ensures that two leaks reported on the same line
@@ -433,19 +492,22 @@
           if (UPDLoc.isValid()) {
             FullSourceLoc UL(SM->getExpansionLoc(UPDLoc.asLocation()),
                              *SM);
-            FullSourceLoc UFunL(SM->getExpansionLoc(
-              D->getUniqueingDecl()->getBody()->getLocStart()), *SM);
             o << "  <key>issue_hash</key><string>"
-              << UL.getExpansionLineNumber() - UFunL.getExpansionLineNumber()
+              << GetHashOfContent(
+                 std::to_string(UL.getExpansionColumnNumber()) + "$" +
+                 ::NormalizeLine(SM, UL, DeclWithIssue) + "$" +
+                 D->getBugType().str())
               << "</string>\n";
 
           // Otherwise, use the location on which the bug is reported.
           } else {
             FullSourceLoc L(SM->getExpansionLoc(D->getLocation().asLocation()),
                             *SM);
-            FullSourceLoc FunL(SM->getExpansionLoc(Body->getLocStart()), *SM);
             o << "  <key>issue_hash</key><string>"
-              << L.getExpansionLineNumber() - FunL.getExpansionLineNumber()
+              << GetHashOfContent(
+                 std::to_string(L.getExpansionColumnNumber()) + "$" +
+                 ::NormalizeLine(SM, L, DeclWithIssue) + "$" +
+                 D->getBugType().str())
               << "</string>\n";
           }