[analyzer] Fix a crash reported in PR 14400.

The AllocaRegion did not have the superRegion (based on LocationContext)
as part of it's hash. As a consequence, the AllocaRegions from
different frames were uniqued to be the same region.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@168599 91177308-0d34-0410-b5e6-96231b3b80d8

lib/StaticAnalyzer/Checkers/BuiltinFunctionChecker.cpp

@@ -68,6 +68,7 @@ bool BuiltinFunctionChecker::evalCall(const CallExpr *CE,
     DefinedOrUnknownSVal extentMatchesSizeArg =
       svalBuilder.evalEQ(state, Extent, Size);
     state = state->assume(extentMatchesSizeArg, true);
+    assert(state && "The region should not have any previous constraints");
 
     C.addTransition(state->BindExpr(CE, LCtx, loc::MemRegionVal(R)));
     return true;

lib/StaticAnalyzer/Core/MemRegion.cpp

@@ -272,10 +272,11 @@ void ObjCStringRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
 
 void AllocaRegion::ProfileRegion(llvm::FoldingSetNodeID& ID,
                                  const Expr *Ex, unsigned cnt,
-                                 const MemRegion *) {
+                                 const MemRegion *superRegion) {
   ID.AddInteger((unsigned) AllocaRegionKind);
   ID.AddPointer(Ex);
   ID.AddInteger(cnt);
+  ID.AddPointer(superRegion);
 }
 
 void AllocaRegion::Profile(llvm::FoldingSetNodeID& ID) const {

test/Analysis/misc-ps-region-store.cpp

@@ -628,3 +628,8 @@ void test_inline() {
   a.bar();
 }
 
+void test_alloca_in_a_recursive_function(int p1) {
+    __builtin_alloca (p1);
+    test_alloca_in_a_recursive_function(1);
+    test_alloca_in_a_recursive_function(2);
+}