vendor/llvm-project/llvmorg-11-init-20887-g2e10b7a39b9vendor/llvm-project/master

1 files changed, 59 insertions, 8 deletions

diff --git a/clang/lib/Sema/AnalysisBasedWarnings.cpp b/clang/lib/Sema/AnalysisBasedWarnings.cpp
index 04611dadde66..3b7356893833 100644
--- a/clang/lib/Sema/AnalysisBasedWarnings.cpp
+++ b/clang/lib/Sema/AnalysisBasedWarnings.cpp
@@ -974,6 +974,14 @@ static void DiagUninitUse(Sema &S, const VarDecl *VD, const UninitUse &Use,
         << Use.getUser()->getSourceRange();
 }
 
+/// Diagnose uninitialized const reference usages.
+static bool DiagnoseUninitializedConstRefUse(Sema &S, const VarDecl *VD,
+                                             const UninitUse &Use) {
+  S.Diag(Use.getUser()->getBeginLoc(), diag::warn_uninit_const_reference)
+      << VD->getDeclName() << Use.getUser()->getSourceRange();
+  return true;
+}
+
 /// DiagnoseUninitializedUse -- Helper function for diagnosing uses of an
 /// uninitialized variable. This manages the different forms of diagnostic
 /// emitted for particular types of uses. Returns true if the use was diagnosed
@@ -1506,13 +1514,14 @@ class UninitValsDiagReporter : public UninitVariablesHandler {
   // order of diagnostics when calling flushDiagnostics().
   typedef llvm::MapVector<const VarDecl *, MappedType> UsesMap;
   UsesMap uses;
+  UsesMap constRefUses;
 
 public:
   UninitValsDiagReporter(Sema &S) : S(S) {}
   ~UninitValsDiagReporter() override { flushDiagnostics(); }
 
-  MappedType &getUses(const VarDecl *vd) {
-    MappedType &V = uses[vd];
+  MappedType &getUses(UsesMap &um, const VarDecl *vd) {
+    MappedType &V = um[vd];
     if (!V.getPointer())
       V.setPointer(new UsesVec());
     return V;
@@ -1520,11 +1529,17 @@ public:
 
   void handleUseOfUninitVariable(const VarDecl *vd,
                                  const UninitUse &use) override {
-    getUses(vd).getPointer()->push_back(use);
+    getUses(uses, vd).getPointer()->push_back(use);
+  }
+
+  void handleConstRefUseOfUninitVariable(const VarDecl *vd,
+                                         const UninitUse &use) override {
+    getUses(constRefUses, vd).getPointer()->push_back(use);
   }
 
   void handleSelfInit(const VarDecl *vd) override {
-    getUses(vd).setInt(true);
+    getUses(uses, vd).setInt(true);
+    getUses(constRefUses, vd).setInt(true);
   }
 
   void flushDiagnostics() {
@@ -1571,6 +1586,32 @@ public:
     }
 
     uses.clear();
+
+    // Flush all const reference uses diags.
+    for (const auto &P : constRefUses) {
+      const VarDecl *vd = P.first;
+      const MappedType &V = P.second;
+
+      UsesVec *vec = V.getPointer();
+      bool hasSelfInit = V.getInt();
+
+      if (!vec->empty() && hasSelfInit && hasAlwaysUninitializedUse(vec))
+        DiagnoseUninitializedUse(S, vd,
+                                 UninitUse(vd->getInit()->IgnoreParenCasts(),
+                                           /* isAlwaysUninit */ true),
+                                 /* alwaysReportSelfInit */ true);
+      else {
+        for (const auto &U : *vec) {
+          if (DiagnoseUninitializedConstRefUse(S, vd, U))
+            break;
+        }
+      }
+
+      // Release the uses vector.
+      delete vec;
+    }
+
+    constRefUses.clear();
   }
 
 private:
@@ -1659,6 +1700,14 @@ class ThreadSafetyReporter : public clang::threadSafety::ThreadSafetyHandler {
                : getNotes();
   }
 
+  OptionalNotes makeUnlockedHereNote(SourceLocation LocUnlocked,
+                                     StringRef Kind) {
+    return LocUnlocked.isValid()
+               ? getNotes(PartialDiagnosticAt(
+                     LocUnlocked, S.PDiag(diag::note_unlocked_here) << Kind))
+               : getNotes();
+  }
+
  public:
   ThreadSafetyReporter(Sema &S, SourceLocation FL, SourceLocation FEL)
     : S(S), FunLocation(FL), FunEndLocation(FEL),
@@ -1685,13 +1734,14 @@ class ThreadSafetyReporter : public clang::threadSafety::ThreadSafetyHandler {
     Warnings.emplace_back(std::move(Warning), getNotes());
   }
 
-  void handleUnmatchedUnlock(StringRef Kind, Name LockName,
-                             SourceLocation Loc) override {
+  void handleUnmatchedUnlock(StringRef Kind, Name LockName, SourceLocation Loc,
+                             SourceLocation LocPreviousUnlock) override {
     if (Loc.isInvalid())
       Loc = FunLocation;
     PartialDiagnosticAt Warning(Loc, S.PDiag(diag::warn_unlock_but_no_lock)
                                          << Kind << LockName);
-    Warnings.emplace_back(std::move(Warning), getNotes());
+    Warnings.emplace_back(std::move(Warning),
+                          makeUnlockedHereNote(LocPreviousUnlock, Kind));
   }
 
   void handleIncorrectUnlockKind(StringRef Kind, Name LockName,
@@ -2184,7 +2234,8 @@ AnalysisBasedWarnings::IssueWarnings(sema::AnalysisBasedWarnings::Policy P,
 
   if (!Diags.isIgnored(diag::warn_uninit_var, D->getBeginLoc()) ||
       !Diags.isIgnored(diag::warn_sometimes_uninit_var, D->getBeginLoc()) ||
-      !Diags.isIgnored(diag::warn_maybe_uninit_var, D->getBeginLoc())) {
+      !Diags.isIgnored(diag::warn_maybe_uninit_var, D->getBeginLoc()) ||
+      !Diags.isIgnored(diag::warn_uninit_const_reference, D->getBeginLoc())) {
     if (CFG *cfg = AC.getCFG()) {
       UninitValsDiagReporter reporter(S);
       UninitVariablesAnalysisStats stats;