[analyzer] Fix a crash until we can handle temporary struct objects properly.

llvm-svn: 124822

clang/lib/StaticAnalyzer/Checkers/ExprEngine.cpp

@@ -1716,7 +1716,11 @@ void ExprEngine::VisitMemberExpr(const MemberExpr* M, ExplodedNode* Pred,
     const GRState* state = GetState(*I);
     SVal baseExprVal = state->getSVal(baseExpr);
     if (isa<nonloc::LazyCompoundVal>(baseExprVal) ||
-        isa<nonloc::CompoundVal>(baseExprVal)) {
+        isa<nonloc::CompoundVal>(baseExprVal) ||
+        // FIXME: This can originate by conjuring a symbol for an unknown
+        // temporary struct object, see test/Analysis/fields.c:
+        // (p = getit()).x
+        isa<nonloc::SymbolVal>(baseExprVal)) {
       MakeNode(Dst, M, *I, state->BindExpr(M, UnknownVal()));
       continue;
     }

clang/test/Analysis/fields.c

@@ -17,3 +17,13 @@ void f() {
   struct s a;
   int *p = &(a.n) + 1;
 }
+
+typedef struct {
+  int x,y;
+} Point;
+
+Point getit(void);
+void test() {
+  Point p;
+  (void)(p = getit()).x;
+}