commit fbdbed3bde8577815826b9d15790e5effb913f7b
author Jordan Rose <jordan_rose@apple.com> Mon Feb 25 19:45:34 2013 +0000
committer Jordan Rose <jordan_rose@apple.com> Mon Feb 25 19:45:34 2013 +0000
tree fdc192c69de3661cf8efffcaaa9c98b988ab34c4
parent 59c900304a390b11c4efcad2924bf6373979db73

[analyzer] Handle reference parameters with default values.

r175026 added support for default values, but didn't take reference
parameters into account, which expect the default argument to be an
lvalue. Use createTemporaryRegionIfNeeded if we can evaluate the default
expr as an rvalue but the expected result is an lvalue.

Fixes the most recent report of PR12915. The original report predates
default argument support, so that can't be it.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176042 91177308-0d34-0410-b5e6-96231b3b80d8

lib/StaticAnalyzer/Core/ExprEngine.cpp

diff --git a/lib/StaticAnalyzer/Core/ExprEngine.cpp b/lib/StaticAnalyzer/Core/ExprEngine.cpp
index eb83e20..8b6de13 100644
--- a/lib/StaticAnalyzer/Core/ExprEngine.cpp
+++ b/lib/StaticAnalyzer/Core/ExprEngine.cpp
@@ -685,7 +685,8 @@
       StmtNodeBuilder Bldr2(PreVisit, Tmp, *currBldrCtx);
 
       const LocationContext *LCtx = Pred->getLocationContext();
-      const Expr *ArgE = cast<CXXDefaultArgExpr>(S)->getExpr();
+      const CXXDefaultArgExpr *DefaultE = cast<CXXDefaultArgExpr>(S);
+      const Expr *ArgE = DefaultE->getExpr();
 
       // Avoid creating and destroying a lot of APSInts.
       SVal V;
@@ -700,7 +701,9 @@
         else
           V = State->getSVal(ArgE, LCtx);
 
-        State = State->BindExpr(S, LCtx, V);
+        State = State->BindExpr(DefaultE, LCtx, V);
+        if (DefaultE->isGLValue())
+          State = createTemporaryRegionIfNeeded(State, LCtx, DefaultE);
         Bldr2.generateNode(S, *I, State);
       }
 

lib/StaticAnalyzer/Core/RegionStore.cpp

diff --git a/lib/StaticAnalyzer/Core/RegionStore.cpp b/lib/StaticAnalyzer/Core/RegionStore.cpp
index 310c080..acda9e0 100644
--- a/lib/StaticAnalyzer/Core/RegionStore.cpp
+++ b/lib/StaticAnalyzer/Core/RegionStore.cpp
@@ -1578,7 +1578,7 @@
     return None;
 
   llvm::APSInt Result;
-  if (Init->EvaluateAsInt(Result, Ctx))
+  if (!Init->isGLValue() && Init->EvaluateAsInt(Result, Ctx))
     return SVB.makeIntVal(Result);
 
   if (Init->isNullPointerConstant(Ctx, Expr::NPC_ValueDependentIsNotNull))

test/Analysis/global_region_invalidation.mm

diff --git a/test/Analysis/global_region_invalidation.mm b/test/Analysis/global_region_invalidation.mm
index 0d7f172..be337ed 100644
--- a/test/Analysis/global_region_invalidation.mm
+++ b/test/Analysis/global_region_invalidation.mm
@@ -9,4 +9,11 @@
   static id p = foo(1); 
     clang_analyzer_eval(p == 0); // expected-warning{{TRUE}}
   return p;
-}
\ No newline at end of file
+}
+
+const int &globalInt = 42;
+
+void testGlobal() {
+  // FIXME: Should be TRUE, but should at least not crash.
+  clang_analyzer_eval(globalInt == 42); // expected-warning{{UNKNOWN}}
+}

test/Analysis/inline.cpp

diff --git a/test/Analysis/inline.cpp b/test/Analysis/inline.cpp
index f0e69dd..27853dc 100644
--- a/test/Analysis/inline.cpp
+++ b/test/Analysis/inline.cpp
@@ -260,6 +260,15 @@
     clang_analyzer_eval(complicatedExprUser(1) == 1); // expected-warning{{TRUE}}
     clang_analyzer_eval(complicatedExprUser() == 84); // expected-warning{{TRUE}}
   }
+
+  int defaultReference(const int &input = 42) {
+    return input;
+  }
+
+  void testReference() {
+    clang_analyzer_eval(defaultReference(1) == 1); // expected-warning{{TRUE}}
+    clang_analyzer_eval(defaultReference() == 42); // expected-warning{{TRUE}}
+  }
 }
 
 namespace OperatorNew {