[analyzer] Ensure BugReporterTracking works on regions with pointer arithmetic

Introduce a new helper function, which computes the first symbolic region in
the base region chain. The corresponding symbol has been used for assuming that
a pointer is null. Now, it will also be used for checking if it is null.

This ensures that we are tracking a null pointer correctly in the BugReporter.

llvm-svn: 179916

1 files changed, 1 insertions, 1 deletions

diff --git a/clang/lib/StaticAnalyzer/Core/ProgramState.cpp b/clang/lib/StaticAnalyzer/Core/ProgramState.cpp
index 4b857b0ac24..5c54e2f112a 100644
--- a/clang/lib/StaticAnalyzer/Core/ProgramState.cpp
+++ b/clang/lib/StaticAnalyzer/Core/ProgramState.cpp
@@ -383,7 +383,7 @@ ConditionTruthVal ProgramState::isNull(SVal V) const {
   if (V.isConstant())
     return false;
   
-  SymbolRef Sym = V.getAsSymbol();
+  SymbolRef Sym = V.getAsSymbol(/* IncludeBaseRegion */ true);
   if (!Sym)
     return ConditionTruthVal();