3 files changed, 9 insertions, 4 deletions
diff --git a/src/corelib/global/qcompilerdetection.h b/src/corelib/global/qcompilerdetection.h
index 5497b9e14a..5fc7ac9c7e 100644
--- a/src/corelib/global/qcompilerdetection.h
+++ b/src/corelib/global/qcompilerdetection.h
@@ -994,6 +994,10 @@
 #  endif /* __cplusplus */
 #endif /* Q_CC_MSVC */
 
+#ifdef Q_COMPILER_UNICODE_STRINGS
+#  define Q_STDLIB_UNICODE_STRINGS
+#endif
+
 #ifdef __cplusplus
 # include <utility>
 # if defined(Q_OS_QNX)
@@ -1016,8 +1020,9 @@
 #    undef Q_COMPILER_INITIALIZER_LISTS
 #    undef Q_COMPILER_RVALUE_REFS
 #    undef Q_COMPILER_REF_QUALIFIERS
-#    undef Q_COMPILER_UNICODE_STRINGS
 #    undef Q_COMPILER_NOEXCEPT
+// Disable C++11 library features:
+#    undef Q_STDLIB_UNICODE_STRINGS
 #   endif // !_HAS_CPP0X
 #   if !defined(_HAS_NULLPTR_T) || !_HAS_NULLPTR_T
 #    undef Q_COMPILER_NULLPTR
diff --git a/src/corelib/io/qdebug.h b/src/corelib/io/qdebug.h
index 61059dd694..186722b69b 100644
--- a/src/corelib/io/qdebug.h
+++ b/src/corelib/io/qdebug.h
@@ -139,7 +139,7 @@ public:
     inline QDebug &operator<<(signed short t) { stream->ts << t; return maybeSpace(); }
     inline QDebug &operator<<(unsigned short t) { stream->ts << t; return maybeSpace(); }
 #ifdef Q_COMPILER_UNICODE_STRINGS
-    inline QDebug &operator<<(char16_t t) { return *this << QChar(t); }
+    inline QDebug &operator<<(char16_t t) { return *this << QChar(ushort(t)); }
     inline QDebug &operator<<(char32_t t) { putUcs4(t); return maybeSpace(); }
 #endif
     inline QDebug &operator<<(signed int t) { stream->ts << t; return maybeSpace(); }
diff --git a/src/corelib/tools/qstring.h b/src/corelib/tools/qstring.h
index f81a58813d..109b68c544 100644
--- a/src/corelib/tools/qstring.h
+++ b/src/corelib/tools/qstring.h
@@ -756,7 +756,7 @@ public:
     static inline QString fromStdWString(const std::wstring &s);
     inline std::wstring toStdWString() const;
 
-#if defined(Q_COMPILER_UNICODE_STRINGS) || defined(Q_QDOC)
+#if defined(Q_STDLIB_UNICODE_STRINGS) || defined(Q_QDOC)
     static inline QString fromStdU16String(const std::u16string &s);
     inline std::u16string toStdU16String() const;
     static inline QString fromStdU32String(const std::u32string &s);
@@ -1339,7 +1339,7 @@ inline std::wstring QString::toStdWString() const
 inline QString QString::fromStdWString(const std::wstring &s)
 { return fromWCharArray(s.data(), int(s.size())); }
 
-#if defined(Q_COMPILER_UNICODE_STRINGS)
+#if defined(Q_STDLIB_UNICODE_STRINGS)
 inline QString QString::fromStdU16String(const std::u16string &s)
 { return fromUtf16(s.data(), int(s.size())); }