Make one-bit bit fields unsigned.

third_party/jsoncpp/overrides/include/json/value.h

Index: third_party/jsoncpp/overrides/include/json/value.h
diff --git a/third_party/jsoncpp/overrides/include/json/value.h b/third_party/jsoncpp/overrides/include/json/value.h
index 1484ee2c4947e00b81108ad4b2b86686a76efdc9..57072602034e81b674e357cefddca45ed578473b 100644
--- a/third_party/jsoncpp/overrides/include/json/value.h
+++ b/third_party/jsoncpp/overrides/include/json/value.h
@@ -496,10 +496,12 @@ namespace Json {
 # endif
       } value_;
       ValueType type_ : 8;
-      int allocated_ : 1;     // Notes: if declared as bool, bitfield is useless.
+      // One-bit bitfields must be unsigned to allow storing 1.
+      // They must be 32-bits to share storage with ValueHolder.
+      unsigned int allocated_ : 1;
 # ifdef JSON_VALUE_USE_INTERNAL_MAP
       unsigned int itemIsUsed_ : 1;      // used by the ValueInternalMap container.
-      int memberNameIsStatic_ : 1;       // used by the ValueInternalMap container.
+      unsigned int memberNameIsStatic_ : 1; // used by the ValueInternalMap container.
 # endif
       CommentInfo *comments_;
    };