Remove ProgramState::getSymVal(). It was being misused by Checkers,

with at least one subtle bug in MacOSXKeyChainAPIChecker where the
calling the method was a substitute for assuming a symbolic value
was null (which is not the case).

We still keep ConstraintManager::getSymVal(), but we use that as
an optimization in SValBuilder and ProgramState::getSVal() to
constant-fold SVals.  This is only if the ConstraintManager can
provide us with that information, which is no longer a requirement.
As part of this, introduce a default implementation of
ConstraintManager::getSymVal() which returns null.

For Checkers, introduce ConstraintManager::isNull(), which queries
the state to see if the symbolic value is constrained to be a null
value.  It does this without assuming it has been implicitly constant
folded.

llvm-svn: 163428

1 files changed, 2 insertions, 2 deletions

diff --git a/clang/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp
index 969f2ddeb4c..21db9e67c14 100644
--- a/clang/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/MacOSKeychainAPIChecker.cpp
@@ -585,7 +585,7 @@ void MacOSKeychainAPIChecker::checkDeadSymbols(SymbolReaper &SR,
     State = State->remove<AllocatedData>(I->first);
     // If the allocated symbol is null or if the allocation call might have
     // returned an error, do not report.
-    if (State->getSymVal(I->first) ||
+    if (State->getConstraintManager().isNull(State, I->first).isTrue() ||
         definitelyReturnedError(I->second.Region, State, C.getSValBuilder()))
       continue;
     Errors.push_back(std::make_pair(I->first, &I->second));
@@ -630,7 +630,7 @@ void MacOSKeychainAPIChecker::checkEndPath(CheckerContext &C) const {
     state = state->remove<AllocatedData>(I->first);
     // If the allocated symbol is null or if error code was returned at
     // allocation, do not report.
-    if (state->getSymVal(I.getKey()) ||
+    if (state->getConstraintManager().isNull(state, I.getKey()).isTrue() ||
         definitelyReturnedError(I->second.Region, state,
                                 C.getSValBuilder())) {
       continue;