Vendor import of clang trunk r256945:vendor/clang/clang-trunk-r256945

https://llvm.org/svn/llvm-project/cfe/trunk@256945

3 files changed, 55 insertions, 20 deletions

diff --git a/lib/StaticAnalyzer/Checkers/DereferenceChecker.cpp b/lib/StaticAnalyzer/Checkers/DereferenceChecker.cpp
index 5dd28320f88f..f216f696ef65 100644
--- a/lib/StaticAnalyzer/Checkers/DereferenceChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/DereferenceChecker.cpp
@@ -34,8 +34,7 @@ class DereferenceChecker
   mutable std::unique_ptr<BuiltinBug> BT_null;
   mutable std::unique_ptr<BuiltinBug> BT_undef;
 
-  void reportBug(ProgramStateRef State, const Stmt *S, CheckerContext &C,
-                 bool IsBind = false) const;
+  void reportBug(ProgramStateRef State, const Stmt *S, CheckerContext &C) const;
 
 public:
   void checkLocation(SVal location, bool isLoad, const Stmt* S,
@@ -89,8 +88,31 @@ DereferenceChecker::AddDerefSource(raw_ostream &os,
   }
 }
 
+static const Expr *getDereferenceExpr(const Stmt *S, bool IsBind=false){
+  const Expr *E = nullptr;
+
+  // Walk through lvalue casts to get the original expression
+  // that syntactically caused the load.
+  if (const Expr *expr = dyn_cast<Expr>(S))
+    E = expr->IgnoreParenLValueCasts();
+
+  if (IsBind) {
+    const VarDecl *VD;
+    const Expr *Init;
+    std::tie(VD, Init) = parseAssignment(S);
+    if (VD && Init)
+      E = Init;
+  }
+  return E;
+}
+
+static bool suppressReport(const Expr *E) {
+  // Do not report dereferences on memory in non-default address spaces.
+  return E->getType().getQualifiers().hasAddressSpace();
+}
+
 void DereferenceChecker::reportBug(ProgramStateRef State, const Stmt *S,
-                                   CheckerContext &C, bool IsBind) const {
+                                   CheckerContext &C) const {
   // Generate an error node.
   ExplodedNode *N = C.generateErrorNode(State);
   if (!N)
@@ -106,19 +128,6 @@ void DereferenceChecker::reportBug(ProgramStateRef State, const Stmt *S,
 
   SmallVector<SourceRange, 2> Ranges;
 
-  // Walk through lvalue casts to get the original expression
-  // that syntactically caused the load.
-  if (const Expr *expr = dyn_cast<Expr>(S))
-    S = expr->IgnoreParenLValueCasts();
-
-  if (IsBind) {
-    const VarDecl *VD;
-    const Expr *Init;
-    std::tie(VD, Init) = parseAssignment(S);
-    if (VD && Init)
-      S = Init;
-  }
-
   switch (S->getStmtClass()) {
   case Stmt::ArraySubscriptExprClass: {
     os << "Array access";
@@ -209,8 +218,11 @@ void DereferenceChecker::checkLocation(SVal l, bool isLoad, const Stmt* S,
   // The explicit NULL case.
   if (nullState) {
     if (!notNullState) {
-      reportBug(nullState, S, C);
-      return;
+      const Expr *expr = getDereferenceExpr(S);
+      if (!suppressReport(expr)) {
+        reportBug(nullState, expr, C);
+        return;
+      }
     }
 
     // Otherwise, we have the case where the location could either be
@@ -248,8 +260,11 @@ void DereferenceChecker::checkBind(SVal L, SVal V, const Stmt *S,
 
   if (StNull) {
     if (!StNonNull) {
-      reportBug(StNull, S, C, /*isBind=*/true);
-      return;
+      const Expr *expr = getDereferenceExpr(S, /*IsBind=*/true);
+      if (!suppressReport(expr)) {
+        reportBug(StNull, expr, C);
+        return;
+      }
     }
 
     // At this point the value could be either null or non-null.
diff --git a/lib/StaticAnalyzer/Checkers/MallocChecker.cpp b/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
index 713d9fe285a5..ce2c19409dc1 100644
--- a/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/MallocChecker.cpp
@@ -2508,6 +2508,16 @@ bool MallocChecker::mayFreeAnyEscapedMemoryOrIsModeledExplicitly(
     return true;
   }
 
+  if (FName == "postEvent" &&
+      FD->getQualifiedNameAsString() == "QCoreApplication::postEvent") {
+    return true;
+  }
+
+  if (FName == "postEvent" &&
+      FD->getQualifiedNameAsString() == "QCoreApplication::postEvent") {
+    return true;
+  }
+
   // Handle cases where we know a buffer's /address/ can escape.
   // Note that the above checks handle some special cases where we know that
   // even though the address escapes, it's still our responsibility to free the
diff --git a/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp b/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
index ec1310d91814..cf1e0a6a656c 100644
--- a/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
+++ b/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
@@ -1542,6 +1542,16 @@ LikelyFalsePositiveSuppressionBRVisitor::getEndPath(BugReporterContext &BRC,
         }
       }
 
+      // The analyzer issues a false positive when the constructor of
+      // std::__independent_bits_engine from algorithms is used.
+      if (const CXXConstructorDecl *MD = dyn_cast<CXXConstructorDecl>(D)) {
+        const CXXRecordDecl *CD = MD->getParent();
+        if (CD->getName() == "__independent_bits_engine") {
+          BR.markInvalid(getTag(), nullptr);
+          return nullptr;
+        }
+      }
+
       // The analyzer issues a false positive on
       //   std::basic_string<uint8_t> v; v.push_back(1);
       // and