Wrap qPrintable inside QString

QString() is a no-op if string is already a QString

And it fixes the compilation if other types are use that do not have
toLocal8Bit such as QStringBuilder.
WebKit trunk has an instance of such usage.

Reviewed-by: Joao

2 files changed, 3 insertions, 1 deletions

diff --git a/src/corelib/global/qglobal.h b/src/corelib/global/qglobal.h
index 67ccf4d..2ddb91d 100644
--- a/src/corelib/global/qglobal.h
+++ b/src/corelib/global/qglobal.h
@@ -1667,7 +1667,7 @@ inline void qUnused(T &x) { (void)x; }
 #endif
 
 #ifndef qPrintable
-#  define qPrintable(string) (string).toLocal8Bit().constData()
+#  define qPrintable(string) QString(string).toLocal8Bit().constData()
 #endif
 
 Q_CORE_EXPORT void qDebug(const char *, ...) /* print debug message */
diff --git a/tests/auto/qstringbuilder1/stringbuilder.cpp b/tests/auto/qstringbuilder1/stringbuilder.cpp
index b4f6334..1ea7347 100644
--- a/tests/auto/qstringbuilder1/stringbuilder.cpp
+++ b/tests/auto/qstringbuilder1/stringbuilder.cpp
@@ -110,4 +110,6 @@ void runScenario()
     r = string P ba;
     QCOMPARE(r, r2);
 #endif
+
+    QCOMPARE(QByteArray(qPrintable(string P string)), QByteArray(string.toLatin1() + string.toLatin1()));
 }