[analyzer] Teach trackNullOrUndefValue about calls to property accessors.

Teach trackNullOrUndefValue() how to look through PseudoObjectExprs to find
the underlying method call for property getters. This makes over-suppression
of 'return nil' in getters consistent with the similar over-suppression for
method and function calls.

rdar://problem/24437252

llvm-svn: 265839

1 files changed, 6 insertions, 0 deletions

diff --git a/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp b/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
index 859a2220e09..e0f014714f7 100644
--- a/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
+++ b/clang/lib/StaticAnalyzer/Core/BugReporterVisitors.cpp
@@ -908,6 +908,12 @@ static const Expr *peelOffOuterExpr(const Expr *Ex,
     return peelOffOuterExpr(EWC->getSubExpr(), N);
   if (const OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(Ex))
     return peelOffOuterExpr(OVE->getSourceExpr(), N);
+  if (auto *POE = dyn_cast<PseudoObjectExpr>(Ex)) {
+    auto *PropRef = dyn_cast<ObjCPropertyRefExpr>(POE->getSyntacticForm());
+    if (PropRef && PropRef->isMessagingGetter()) {
+      return peelOffOuterExpr(POE->getSemanticExpr(1), N);
+    }
+  }
 
   // Peel off the ternary operator.
   if (const ConditionalOperator *CO = dyn_cast<ConditionalOperator>(Ex)) {