Merge remote-tracking branch 'origin/5.13' into 5.14

 Conflicts:
	src/corelib/global/qrandom.cpp
	src/corelib/io/qfileinfo.cpp
	src/corelib/kernel/qeventdispatcher_win.cpp
	src/corelib/kernel/qeventdispatcher_win_p.h
	src/gui/text/qfontdatabase.cpp
	src/platformsupport/fontdatabases/mac/qcoretextfontdatabase.mm
	src/plugins/platforms/windows/qwindowsglcontext.cpp
	src/testlib/qtestcase.cpp

Done-With: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
Done-With: Edward Welbourne <edward.welbourne@qt.io>
Change-Id: I4893212471aa24be804c989a581810e2f714545c

8 files changed, 168 insertions, 64 deletions

diff --git a/src/corelib/doc/snippets/code/src_corelib_kernel_qobject.cpp b/src/corelib/doc/snippets/code/src_corelib_kernel_qobject.cpp
index 1e31a5292f..1966f8195a 100644
--- a/src/corelib/doc/snippets/code/src_corelib_kernel_qobject.cpp
+++ b/src/corelib/doc/snippets/code/src_corelib_kernel_qobject.cpp
@@ -416,7 +416,7 @@ public:
         LoadArchiveMemberHint = 0x04
     };
     Q_DECLARE_FLAGS(LoadHints, LoadHint)
-    Q_FLAG(LoadHints)
+    Q_FLAG(LoadHint)
     ...
 }
 //! [39]
diff --git a/src/corelib/global/qrandom.cpp b/src/corelib/global/qrandom.cpp
index e5b2399566..3cbd40b772 100644
--- a/src/corelib/global/qrandom.cpp
+++ b/src/corelib/global/qrandom.cpp
@@ -90,47 +90,6 @@ DECLSPEC_IMPORT BOOLEAN WINAPI SystemFunction036(PVOID RandomBuffer, ULONG Rando
 
 QT_BEGIN_NAMESPACE
 
-#if defined(Q_PROCESSOR_X86) && QT_COMPILER_SUPPORTS_HERE(RDRND)
-static qsizetype qt_random_cpu(void *buffer, qsizetype count) noexcept;
-
-#  ifdef Q_PROCESSOR_X86_64
-#    define _rdrandXX_step _rdrand64_step
-#  else
-#    define _rdrandXX_step _rdrand32_step
-#  endif
-
-static QT_FUNCTION_TARGET(RDRND) qsizetype qt_random_cpu(void *buffer, qsizetype count) noexcept
-{
-    unsigned *ptr = reinterpret_cast<unsigned *>(buffer);
-    unsigned *end = ptr + count;
-    int retries = 10;
-
-    while (ptr + sizeof(qregisteruint)/sizeof(*ptr) <= end) {
-        if (_rdrandXX_step(reinterpret_cast<qregisteruint *>(ptr)))
-            ptr += sizeof(qregisteruint)/sizeof(*ptr);
-        else if (--retries == 0)
-            goto out;
-    }
-
-    while (sizeof(*ptr) != sizeof(qregisteruint) && ptr != end) {
-        bool ok = _rdrand32_step(ptr);
-        if (!ok && --retries)
-            continue;
-        if (ok)
-            ++ptr;
-        break;
-    }
-
-out:
-    return ptr - reinterpret_cast<unsigned *>(buffer);
-}
-#else
-static qsizetype qt_random_cpu(void *, qsizetype)
-{
-    return 0;
-}
-#endif
-
 enum {
     // may be "overridden" by a member enum
     FillBufferNoexcept = true
@@ -371,8 +330,8 @@ Q_NEVER_INLINE void QRandomGenerator::SystemGenerator::generate(quint32 *begin,
     }
 
     qsizetype filled = 0;
-    if (qt_has_hwrng() && (uint(qt_randomdevice_control.loadAcquire()) & SkipHWRNG) == 0)
-        filled += qt_random_cpu(buffer, count);
+    if (qHasHwrng() && (uint(qt_randomdevice_control.loadAcquire()) & SkipHWRNG) == 0)
+        filled += qRandomCpu(buffer, count);
 
     if (filled != count && (uint(qt_randomdevice_control.loadAcquire()) & SkipSystemRNG) == 0) {
         qsizetype bytesFilled =
diff --git a/src/corelib/global/qrandom_p.h b/src/corelib/global/qrandom_p.h
index 167f4cc57d..934a9282b8 100644
--- a/src/corelib/global/qrandom_p.h
+++ b/src/corelib/global/qrandom_p.h
@@ -81,14 +81,6 @@ static const struct {
 } qt_randomdevice_control;
 #endif
 
-inline bool qt_has_hwrng()
-{
-#if defined(Q_PROCESSOR_X86) && QT_COMPILER_SUPPORTS_HERE(RDRND)
-    return qCpuHasFeature(RDRND);
-#else
-    return false;
-#endif
-}
 
 
 QT_END_NAMESPACE
diff --git a/src/corelib/io/qfileinfo.cpp b/src/corelib/io/qfileinfo.cpp
index a6f8b45ea3..89834de29f 100644
--- a/src/corelib/io/qfileinfo.cpp
+++ b/src/corelib/io/qfileinfo.cpp
@@ -249,16 +249,18 @@ QDateTime &QFileInfoPrivate::getFileTime(QAbstractFileEngine::FileTime request)
     isSymLink(). The symLinkTarget() function provides the name of the file
     the symlink points to.
 
-    On Unix (including \macos and iOS), the symlink has the same size() has
-    the file it points to, because Unix handles symlinks
-    transparently; similarly, opening a symlink using QFile
-    effectively opens the link's target. For example:
+    On Unix (including \macos and iOS), the property getter functions in this
+    class return the properties such as times and size of the target file, not
+    the symlink, because Unix handles symlinks transparently. Opening a symlink
+    using QFile effectively opens the link's target. For example:
 
     \snippet code/src_corelib_io_qfileinfo.cpp 0
 
-    On Windows, shortcuts are \c .lnk files. The reported size() is that of
-    the shortcut (not the link's target), and opening a shortcut using QFile
-    opens the \c .lnk file. For example:
+    On Windows, shortcuts (\c .lnk files) are currently treated as symlinks. As
+    on Unix systems, the property getters return the size of the targeted file,
+    not the \c .lnk file itself.  This behavior is deprecated and will likely be
+    removed in a future version of Qt, after which \c .lnk files will be treated
+    as regular files.
 
     \snippet code/src_corelib_io_qfileinfo.cpp 1
 
@@ -903,6 +905,9 @@ QDir QFileInfo::absoluteDir() const
 /*!
     Returns \c true if the user can read the file; otherwise returns \c false.
 
+    If the file is a symlink, this function returns true if the target is
+    readable (not the symlink).
+
     \note If the \l{NTFS permissions} check has not been enabled, the result
     on Windows will merely reflect whether the file exists.
 
@@ -920,6 +925,9 @@ bool QFileInfo::isReadable() const
 /*!
     Returns \c true if the user can write to the file; otherwise returns \c false.
 
+    If the file is a symlink, this function returns true if the target is
+    writeable (not the symlink).
+
     \note If the \l{NTFS permissions} check has not been enabled, the result on
     Windows will merely reflect whether the file is marked as Read Only.
 
@@ -937,6 +945,9 @@ bool QFileInfo::isWritable() const
 /*!
     Returns \c true if the file is executable; otherwise returns \c false.
 
+    If the file is a symlink, this function returns true if the target is
+    executable (not the symlink).
+
     \sa isReadable(), isWritable(), permission()
 */
 bool QFileInfo::isExecutable() const
@@ -951,8 +962,13 @@ bool QFileInfo::isExecutable() const
 /*!
     Returns \c true if this is a `hidden' file; otherwise returns \c false.
 
-    \b{Note:} This function returns \c true for the special entries
-    "." and ".." on Unix, even though QDir::entryList threats them as shown.
+    \b{Note:} This function returns \c true for the special entries "." and
+    ".." on Unix, even though QDir::entryList threats them as shown. And note
+    that, since this function inspects the file name, on Unix it will inspect
+    the name of the symlink, if this file is a symlink, not the target's name.
+
+    On Windows, this function returns \c true if the target file is hidden (not
+    the symlink).
 */
 bool QFileInfo::isHidden() const
 {
@@ -991,6 +1007,9 @@ bool QFileInfo::isNativePath() const
     link to a file. Returns \c false if the
     object points to something which isn't a file, such as a directory.
 
+    If the file is a symlink, this function returns true if the target is a
+    regular file (not the symlink).
+
     \sa isDir(), isSymLink(), isBundle()
 */
 bool QFileInfo::isFile() const
@@ -1006,6 +1025,9 @@ bool QFileInfo::isFile() const
     Returns \c true if this object points to a directory or to a symbolic
     link to a directory; otherwise returns \c false.
 
+    If the file is a symlink, this function returns true if the target is a
+    directory (not the symlink).
+
     \sa isFile(), isSymLink(), isBundle()
 */
 bool QFileInfo::isDir() const
@@ -1023,6 +1045,9 @@ bool QFileInfo::isDir() const
     Returns \c true if this object points to a bundle or to a symbolic
     link to a bundle on \macos and iOS; otherwise returns \c false.
 
+    If the file is a symlink, this function returns true if the target is a
+    bundle (not the symlink).
+
     \sa isDir(), isSymLink(), isFile()
 */
 bool QFileInfo::isBundle() const
@@ -1044,7 +1069,8 @@ bool QFileInfo::isBundle() const
     the \l{symLinkTarget()}{link's target}.
 
     In addition, true will be returned for shortcuts (\c *.lnk files) on
-    Windows. Opening those will open the \c .lnk file itself.
+    Windows. This behavior is deprecated and will likely change in a future
+    version of Qt. Opening those will open the \c .lnk file itself.
 
     Example:
 
@@ -1190,6 +1216,9 @@ QString QFileInfo::symLinkTarget() const
     milliseconds). On Windows, it will return an empty string unless
     the \l{NTFS permissions} check has been enabled.
 
+    If the file is a symlink, this function returns the owner of the target
+    (not the symlink).
+
     \sa ownerId(), group(), groupId()
 */
 QString QFileInfo::owner() const
@@ -1206,6 +1235,9 @@ QString QFileInfo::owner() const
     On Windows and on systems where files do not have owners this
     function returns ((uint) -2).
 
+    If the file is a symlink, this function returns the id of the owner of the target
+    (not the symlink).
+
     \sa owner(), group(), groupId()
 */
 uint QFileInfo::ownerId() const
@@ -1225,6 +1257,9 @@ uint QFileInfo::ownerId() const
     This function can be time consuming under Unix (in the order of
     milliseconds).
 
+    If the file is a symlink, this function returns the owning group of the
+    target (not the symlink).
+
     \sa groupId(), owner(), ownerId()
 */
 QString QFileInfo::group() const
@@ -1241,6 +1276,9 @@ QString QFileInfo::group() const
     On Windows and on systems where files do not have groups this
     function always returns (uint) -2.
 
+    If the file is a symlink, this function returns the id of the group owning the
+    target (not the symlink).
+
     \sa group(), owner(), ownerId()
 */
 uint QFileInfo::groupId() const
@@ -1266,6 +1304,9 @@ uint QFileInfo::groupId() const
     Example:
     \snippet code/src_corelib_io_qfileinfo.cpp 10
 
+    If the file is a symlink, this function checks the permissions of the
+    target (not the symlink).
+
     \sa isReadable(), isWritable(), isExecutable()
 */
 bool QFileInfo::permission(QFile::Permissions permissions) const
@@ -1288,6 +1329,9 @@ bool QFileInfo::permission(QFile::Permissions permissions) const
 
     \note The result might be inaccurate on Windows if the
     \l{NTFS permissions} check has not been enabled.
+
+    If the file is a symlink, this function returns the permissions of the
+    target (not the symlink).
 */
 QFile::Permissions QFileInfo::permissions() const
 {
@@ -1305,6 +1349,9 @@ QFile::Permissions QFileInfo::permissions() const
     Returns the file size in bytes. If the file does not exist or cannot be
     fetched, 0 is returned.
 
+    If the file is a symlink, the size of the target file is returned
+    (not the symlink).
+
     \sa exists()
 */
 qint64 QFileInfo::size() const
@@ -1334,6 +1381,9 @@ qint64 QFileInfo::size() const
     the time the file was created, metadataChangeTime() to get the time its
     metadata was last changed, or lastModified() to get the time it was last modified.
 
+    If the file is a symlink, the time of the target file is returned
+    (not the symlink).
+
     \sa birthTime(), metadataChangeTime(), lastModified(), lastRead()
 */
 QDateTime QFileInfo::created() const
@@ -1352,6 +1402,9 @@ QDateTime QFileInfo::created() const
     If the file birth time is not available, this function returns an invalid
     QDateTime.
 
+    If the file is a symlink, the time of the target file is returned
+    (not the symlink).
+
     \sa lastModified(), lastRead(), metadataChangeTime()
 */
 QDateTime QFileInfo::birthTime() const
@@ -1366,6 +1419,9 @@ QDateTime QFileInfo::birthTime() const
     user writes or sets inode information (for example, changing the file
     permissions).
 
+    If the file is a symlink, the time of the target file is returned
+    (not the symlink).
+
     \sa lastModified(), lastRead()
 */
 QDateTime QFileInfo::metadataChangeTime() const
@@ -1376,6 +1432,9 @@ QDateTime QFileInfo::metadataChangeTime() const
 /*!
     Returns the date and local time when the file was last modified.
 
+    If the file is a symlink, the time of the target file is returned
+    (not the symlink).
+
     \sa birthTime(), lastRead(), metadataChangeTime(), fileTime()
 */
 QDateTime QFileInfo::lastModified() const
@@ -1389,6 +1448,9 @@ QDateTime QFileInfo::lastModified() const
     On platforms where this information is not available, returns the
     same as lastModified().
 
+    If the file is a symlink, the time of the target file is returned
+    (not the symlink).
+
     \sa birthTime(), lastModified(), metadataChangeTime(), fileTime()
 */
 QDateTime QFileInfo::lastRead() const
@@ -1402,6 +1464,9 @@ QDateTime QFileInfo::lastRead() const
     Returns the file time specified by \a time. If the time cannot be
     determined, an invalid date time is returned.
 
+    If the file is a symlink, the time of the target file is returned
+    (not the symlink).
+
     \sa QFile::FileTime, QDateTime::isValid()
 */
 QDateTime QFileInfo::fileTime(QFile::FileTime time) const
diff --git a/src/corelib/io/qfilesystemiterator_unix.cpp b/src/corelib/io/qfilesystemiterator_unix.cpp
index 2d09c277eb..74b7e820d9 100644
--- a/src/corelib/io/qfilesystemiterator_unix.cpp
+++ b/src/corelib/io/qfilesystemiterator_unix.cpp
@@ -69,7 +69,9 @@ static bool checkNameDecodable(const char *d_name, qsizetype len)
 #  ifdef QT_LOCALE_IS_UTF8
     int mibEnum = 106;
 #  else
-    int mibEnum = codec->mibEnum();
+    int mibEnum = 4;                // Latin 1
+    if (codec)
+        mibEnum = codec->mibEnum();
 #  endif
     if (Q_LIKELY(mibEnum == 106))   // UTF-8
         return QUtf8::isValidUtf8(d_name, len).isValidUtf8;
diff --git a/src/corelib/tools/qsimd.cpp b/src/corelib/tools/qsimd.cpp
index ecf1822e42..fb9b5996f6 100644
--- a/src/corelib/tools/qsimd.cpp
+++ b/src/corelib/tools/qsimd.cpp
@@ -376,6 +376,38 @@ static quint64 detectProcessorFeatures()
         features &= ~AllAVX512;
     }
 
+#if defined(Q_PROCESSOR_X86) && QT_COMPILER_SUPPORTS_HERE(RDRND)
+    /**
+     * Some AMD CPUs (e.g. AMD A4-6250J and AMD Ryzen 3000-series) have a
+     * failing random generation instruction, which always returns
+     * 0xffffffff, even when generation was "successful".
+     *
+     * This code checks if hardware random generator generates four consecutive
+     * equal numbers. If it does, then we probably have a failing one and
+     * should disable it completely.
+     *
+     * https://bugreports.qt.io/browse/QTBUG-69423
+     */
+    if (features & CpuFeatureRDRND) {
+        const qsizetype testBufferSize = 4;
+        unsigned testBuffer[4] = {};
+
+        const qsizetype generated = qRandomCpu(testBuffer, testBufferSize);
+
+        if (Q_UNLIKELY(generated == testBufferSize &&
+            testBuffer[0] == testBuffer[1] &&
+            testBuffer[1] == testBuffer[2] &&
+            testBuffer[2] == testBuffer[3])) {
+
+            fprintf(stderr, "WARNING: CPU random generator seem to be failing, disable hardware random number generation\n");
+            fprintf(stderr, "WARNING: RDRND generated: 0x%x 0x%x 0x%x 0x%x\n",
+                    testBuffer[0], testBuffer[1], testBuffer[2], testBuffer[3]);
+
+            features &= ~CpuFeatureRDRND;
+        }
+    }
+#endif
+
     return features;
 }
 
@@ -590,4 +622,40 @@ void qDumpCPUFeatures()
     puts("");
 }
 
+#if defined(Q_PROCESSOR_X86) && QT_COMPILER_SUPPORTS_HERE(RDRND)
+
+#  ifdef Q_PROCESSOR_X86_64
+#    define _rdrandXX_step _rdrand64_step
+#  else
+#    define _rdrandXX_step _rdrand32_step
+#  endif
+
+QT_FUNCTION_TARGET(RDRND) qsizetype qRandomCpu(void *buffer, qsizetype count) noexcept
+{
+    unsigned *ptr = reinterpret_cast<unsigned *>(buffer);
+    unsigned *end = ptr + count;
+    int retries = 10;
+
+    while (ptr + sizeof(qregisteruint)/sizeof(*ptr) <= end) {
+        if (_rdrandXX_step(reinterpret_cast<qregisteruint *>(ptr)))
+            ptr += sizeof(qregisteruint)/sizeof(*ptr);
+        else if (--retries == 0)
+            goto out;
+    }
+
+    while (sizeof(*ptr) != sizeof(qregisteruint) && ptr != end) {
+        bool ok = _rdrand32_step(ptr);
+        if (!ok && --retries)
+            continue;
+        if (ok)
+            ++ptr;
+        break;
+    }
+
+out:
+    return ptr - reinterpret_cast<unsigned *>(buffer);
+}
+#endif
+
+
 QT_END_NAMESPACE
diff --git a/src/corelib/tools/qsimd_p.h b/src/corelib/tools/qsimd_p.h
index db2f546651..c28624a25e 100644
--- a/src/corelib/tools/qsimd_p.h
+++ b/src/corelib/tools/qsimd_p.h
@@ -346,6 +346,15 @@ extern Q_CORE_EXPORT QBasicAtomicInteger<unsigned> qt_cpu_features[2];
 #endif
 Q_CORE_EXPORT quint64 qDetectCpuFeatures();
 
+#if defined(Q_PROCESSOR_X86) && QT_COMPILER_SUPPORTS_HERE(RDRND)
+Q_CORE_EXPORT qsizetype qRandomCpu(void *, qsizetype) noexcept;
+#else
+static inline qsizetype qRandomCpu(void *, qsizetype) noexcept
+{
+    return 0;
+}
+#endif
+
 static inline quint64 qCpuFeatures()
 {
     quint64 features = qt_cpu_features[0].loadRelaxed();
@@ -362,6 +371,15 @@ static inline quint64 qCpuFeatures()
 #define qCpuHasFeature(feature)     (((qCompilerCpuFeatures & CpuFeature ## feature) == CpuFeature ## feature) \
                                      || ((qCpuFeatures() & CpuFeature ## feature) == CpuFeature ## feature))
 
+inline bool qHasHwrng()
+{
+#if defined(Q_PROCESSOR_X86) && QT_COMPILER_SUPPORTS_HERE(RDRND)
+    return qCpuHasFeature(RDRND);
+#else
+    return false;
+#endif
+}
+
 #define ALIGNMENT_PROLOGUE_16BYTES(ptr, i, length) \
     for (; i < static_cast<int>(qMin(static_cast<quintptr>(length), ((4 - ((reinterpret_cast<quintptr>(ptr) >> 2) & 0x3)) & 0x3))); ++i)
 
diff --git a/src/corelib/tools/qvarlengtharray.h b/src/corelib/tools/qvarlengtharray.h
index 253d05ba2b..6be695e317 100644
--- a/src/corelib/tools/qvarlengtharray.h
+++ b/src/corelib/tools/qvarlengtharray.h
@@ -104,7 +104,7 @@ public:
 
     QVarLengthArray<T, Prealloc> &operator=(std::initializer_list<T> list)
     {
-        resize(list.size());
+        resize(int(list.size())); // ### q6sizetype
         std::copy(list.begin(), list.end(),
                   QT_MAKE_CHECKED_ARRAY_ITERATOR(this->begin(), this->size()));
         return *this;