Fixes layouting regression and invalid-read.

Layouting would prevent breaking before + in
a[b + c] = d;
Regression detected by code review.

Also fixes an invalid-read found by the valgrind bot.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173262 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Format/Format.cpp b/lib/Format/Format.cpp
index d95deb5..2952067 100644
--- a/lib/Format/Format.cpp
+++ b/lib/Format/Format.cpp
@@ -1256,8 +1256,10 @@
       IsExpression = true;
       AnnotatedToken *Previous = Current.Parent;
       while (Previous != NULL) {
-        if (Previous->Type == TT_BinaryOperator)
+        if (Previous->Type == TT_BinaryOperator &&
+            (Previous->is(tok::star) || Previous->is(tok::amp))) {
           Previous->Type = TT_PointerOrReference;
+        }
         Previous = Previous->Parent;
       }
     }
diff --git a/lib/Format/UnwrappedLineParser.cpp b/lib/Format/UnwrappedLineParser.cpp
index c21fa0d..1b39442 100644
--- a/lib/Format/UnwrappedLineParser.cpp
+++ b/lib/Format/UnwrappedLineParser.cpp
@@ -38,7 +38,10 @@
   }
   ~ScopedDeclarationState() {
     Stack.pop_back();
-    Line.MustBeDeclaration = Stack.back();
+    if (!Stack.empty())
+      Line.MustBeDeclaration = Stack.back();
+    else
+      Line.MustBeDeclaration = true;
   }
 private:
   UnwrappedLine &Line;
diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp
index d1af838..806a7eb 100644
--- a/unittests/Format/FormatTest.cpp
+++ b/unittests/Format/FormatTest.cpp
@@ -1365,6 +1365,13 @@
   verifyGoogleFormat("A = new SomeType* [Length]();");
 }
 
+TEST_F(FormatTest, FormatsBinaryOperatorsPrecedingEquals) {
+  verifyFormat("void f() {\n"
+               "  x[aaaaaaaaa -\n"
+               "      b] = 23;\n"
+               "}", getLLVMStyleWithColumns(15));
+}
+
 TEST_F(FormatTest, FormatsCasts) {
   verifyFormat("Type *A = static_cast<Type *>(P);");
   verifyFormat("Type *A = (Type *)P;");