QByteArray: deprecate QT_NO_CAST_FROM_BYTEARRAY-protected operators

The QByteArray::operator const {char,void}*() implicit
conversions are a source of subtle bugs, so they right-
fully can be disabled with QT_NO_CAST_FROM_BYTEARRAY.

  const char *d = qstring.toLatin1(); // implicit conversion
  while ( d ) // oops: d points to freed memory
     // ...

But almost no-one ever enabled this macros in the wild
and many were bitten by these implicit conversions, so
this patch deprecates them.

I would have liked to remove them completely, but there
are just too many occurrences even in Qt itself to hope
to find all conditionally-compiled code that uses these.

Also fixes all code that needs to compile under
QT_NO_DEPRECATED (in qmake/, src/tools/).

I984706452db7d0841620a0f64e179906123f3849 separately
deals with the bulk of changes in src/ and examples/.

Depends on I5ea1ad3c96d9e64167be53c0c418c7b7dba51f68.

Change-Id: I8d47e6c293c80f61c6288c9f8d42fda41afe2267
Reviewed-by: David Faure <faure@kde.org>
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>

4 files changed, 10 insertions, 12 deletions

diff --git a/src/corelib/tools/qbytearray.cpp b/src/corelib/tools/qbytearray.cpp
index c74c61999d..1d37f578b8 100644
--- a/src/corelib/tools/qbytearray.cpp
+++ b/src/corelib/tools/qbytearray.cpp
@@ -343,7 +343,7 @@ int qstrcmp(const QByteArray &str1, const QByteArray &str2)
 {
     int l1 = str1.length();
     int l2 = str2.length();
-    int ret = memcmp(str1, str2, qMin(l1, l2));
+    int ret = memcmp(str1.constData(), str2.constData(), qMin(l1, l2));
     if (ret != 0)
         return ret;
 
@@ -995,6 +995,8 @@ QByteArray &QByteArray::operator=(const char *str)
 /*! \fn QByteArray::operator const char *() const
     \fn QByteArray::operator const void *() const
 
+    \obsolete Use constData() instead.
+
     Returns a pointer to the data stored in the byte array. The
     pointer can be used to access the bytes that compose the array.
     The data is '\\0'-terminated. The pointer remains valid as long
@@ -2751,7 +2753,7 @@ QDataStream &operator<<(QDataStream &out, const QByteArray &ba)
         out << (quint32)0xffffffff;
         return out;
     }
-    return out.writeBytes(ba, ba.size());
+    return out.writeBytes(ba.constData(), ba.size());
 }
 
 /*! \relates QByteArray
diff --git a/src/corelib/tools/qbytearray.h b/src/corelib/tools/qbytearray.h
index 8202097da5..09c43988fd 100644
--- a/src/corelib/tools/qbytearray.h
+++ b/src/corelib/tools/qbytearray.h
@@ -207,8 +207,10 @@ public:
     void squeeze();
 
 #ifndef QT_NO_CAST_FROM_BYTEARRAY
-    operator const char *() const;
-    operator const void *() const;
+#if QT_DEPRECATED_SINCE(5, 0)
+    QT_DEPRECATED operator const char *() const { return constData(); }
+    QT_DEPRECATED operator const void *() const { return constData(); }
+#endif
 #endif
     char *data();
     const char *data() const;
@@ -415,12 +417,6 @@ inline char QByteArray::operator[](uint i) const
 
 inline bool QByteArray::isEmpty() const
 { return d->size == 0; }
-#ifndef QT_NO_CAST_FROM_BYTEARRAY
-inline QByteArray::operator const char *() const
-{ return d->data(); }
-inline QByteArray::operator const void *() const
-{ return d->data(); }
-#endif
 inline char *QByteArray::data()
 { detach(); return d->data(); }
 inline const char *QByteArray::data() const
diff --git a/src/corelib/tools/qlocale_unix.cpp b/src/corelib/tools/qlocale_unix.cpp
index 6ace96f771..f2876912b4 100644
--- a/src/corelib/tools/qlocale_unix.cpp
+++ b/src/corelib/tools/qlocale_unix.cpp
@@ -98,7 +98,7 @@ QLocale QSystemLocale::fallbackLocale() const
         lang = qgetenv("LC_NUMERIC");
     if (lang.isEmpty())
         lang = qgetenv("LANG");
-    return QLocale(QLatin1String(lang));
+    return QLocale(QString::fromLatin1(lang));
 }
 
 QVariant QSystemLocale::query(QueryType type, QVariant in) const
diff --git a/src/corelib/tools/qstring.cpp b/src/corelib/tools/qstring.cpp
index 704545667c..14b8782dae 100644
--- a/src/corelib/tools/qstring.cpp
+++ b/src/corelib/tools/qstring.cpp
@@ -4761,7 +4761,7 @@ int QString::localeAwareCompare_helper(const QChar *data1, int length1,
     } // else fall through
 #  endif
     // declared in <string.h>
-    int delta = strcoll(toLocal8Bit_helper(data1, length1), toLocal8Bit_helper(data2, length2));
+    int delta = strcoll(toLocal8Bit_helper(data1, length1).constData(), toLocal8Bit_helper(data2, length2).constData());
     if (delta == 0)
         delta = ucstrcmp(data1, length1, data2, length2);
     return delta;