[analyzer] do not warn about returning stack-allocated memory when it comes from an ancestor stack frame.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@151964 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp b/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp
index d071ef8..8c76cc5 100644
--- a/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/StackAddrEscapeChecker.cpp
@@ -113,7 +113,7 @@
}
void StackAddrEscapeChecker::checkPreStmt(const ReturnStmt *RS,
- CheckerContext &C) const {
+ CheckerContext &C) const {
const Expr *RetE = RS->getRetValue();
if (!RetE)
@@ -122,18 +122,26 @@
SVal V = C.getState()->getSVal(RetE, C.getLocationContext());
const MemRegion *R = V.getAsRegion();
- if (!R || !R->hasStackStorage())
- return;
-
- if (R->hasStackStorage()) {
- // Automatic reference counting automatically copies blocks.
- if (C.getASTContext().getLangOptions().ObjCAutoRefCount &&
- isa<BlockDataRegion>(R))
- return;
-
- EmitStackError(C, R, RetE);
+ if (!R)
return;
- }
+
+ const StackSpaceRegion *SS =
+ dyn_cast_or_null<StackSpaceRegion>(R->getMemorySpace());
+
+ if (!SS)
+ return;
+
+ // Return stack memory in an ancestor stack frame is fine.
+ const StackFrameContext *SFC = SS->getStackFrame();
+ if (SFC != C.getLocationContext()->getCurrentStackFrame())
+ return;
+
+ // Automatic reference counting automatically copies blocks.
+ if (C.getASTContext().getLangOptions().ObjCAutoRefCount &&
+ isa<BlockDataRegion>(R))
+ return;
+
+ EmitStackError(C, R, RetE);
}
void StackAddrEscapeChecker::checkEndPath(CheckerContext &Ctx) const {