QCborValue::fromJsonValue: rewrite code to remove UB

Converting an out-of-range FP to integer is UB. See comment in
qnumeric_p.h.

Change-Id: Ief874765cd7b43798de3fffd15a9bfe2c5fbbc01
Reviewed-by: Marc Mutz <marc.mutz@kdab.com>
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>
 
 

1 files changed, 6 insertions, 4 deletions

diff --git a/src/corelib/serialization/qjsoncbor.cpp b/src/corelib/serialization/qjsoncbor.cpp
index 4f756df97c..4603750d11 100644
--- a/src/corelib/serialization/qjsoncbor.cpp
+++ b/src/corelib/serialization/qjsoncbor.cpp
@@ -1,6 +1,6 @@
 /****************************************************************************
 **
-** Copyright (C) 2018 Intel Corporation.
+** Copyright (C) 2019 Intel Corporation.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the QtCore module of the Qt Toolkit.
@@ -598,10 +598,12 @@ QCborValue QCborValue::fromJsonValue(const QJsonValue &v)
     switch (v.type()) {
     case QJsonValue::Bool:
         return v.b;
-    case QJsonValue::Double:
-        if (v.dbl == qint64(v.dbl))
-            return qint64(v.dbl);
+    case QJsonValue::Double: {
+        qint64 i;
+        if (convertDoubleTo(v.dbl, &i))
+            return i;
         return v.dbl;
+    }
     case QJsonValue::String:
         return v.toString();
     case QJsonValue::Array: