Fix:

<rdar://problem/6914474> checker doesn't realize that variable might
have been assigned if a pointer to that variable was passed to another
function via a structure

The problem here was the RegionStoreManager::InvalidateRegion didn't
invalidate the bindings of invalidated regions.  This required a
rewrite of this method using a worklist.

As part of this fix, changed ValueManager::getConjuredSymbolVal() to
require a 'void*' SymbolTag argument.  This tag is used to
differentiate two different symbols created at the same location.

llvm-svn: 82920
diff --git a/clang/lib/Analysis/ValueManager.cpp b/clang/lib/Analysis/ValueManager.cpp
index 9c3dbdd..fe670e7 100644
--- a/clang/lib/Analysis/ValueManager.cpp
+++ b/clang/lib/Analysis/ValueManager.cpp
@@ -88,13 +88,15 @@
   return nonloc::SymbolVal(sym);
 }
 
-DefinedOrUnknownSVal ValueManager::getConjuredSymbolVal(const Expr *E, unsigned Count) {
+DefinedOrUnknownSVal ValueManager::getConjuredSymbolVal(const void *SymbolTag,
+                                                        const Expr *E,
+                                                        unsigned Count) {
   QualType T = E->getType();
 
   if (!SymbolManager::canSymbolicate(T))
     return UnknownVal();
 
-  SymbolRef sym = SymMgr.getConjuredSymbol(E, Count);
+  SymbolRef sym = SymMgr.getConjuredSymbol(E, Count, SymbolTag);
 
   if (Loc::IsLocType(T))
     return loc::MemRegionVal(MemMgr.getSymbolicRegion(sym));
@@ -102,14 +104,15 @@
   return nonloc::SymbolVal(sym);
 }
 
-DefinedOrUnknownSVal ValueManager::getConjuredSymbolVal(const Expr *E,
+DefinedOrUnknownSVal ValueManager::getConjuredSymbolVal(const void *SymbolTag,
+                                                        const Expr *E,
                                                         QualType T,
                                                         unsigned Count) {
   
   if (!SymbolManager::canSymbolicate(T))
     return UnknownVal();
 
-  SymbolRef sym = SymMgr.getConjuredSymbol(E, T, Count);
+  SymbolRef sym = SymMgr.getConjuredSymbol(E, T, Count, SymbolTag);
 
   if (Loc::IsLocType(T))
     return loc::MemRegionVal(MemMgr.getSymbolicRegion(sym));