Mark all of Qt as free of Q_FOREACH, except where it isn't

The density of Q_FOREACH uses in this and some other modules is still
extremely high, too high for anyone to tackle in a short amount of
time. Even if they're not concentrated in just a few TUs, we need to
make progress on a global QT_NO_FOREACH default, so grab the nettle
and stick to our strategy:

Mark the whole of Qt with QT_NO_FOREACH, to prevent new uses from
creeping in, and whitelist the affected TUs by #undef'ing
QT_NO_FOREACH locally, at the top of each file. For TUs that are part
of a larger executable, this requires these files to be compiled
separately, so add them to NO_PCH_SOURCES (which implies
NO_UNITY_BUILD_SOURCES, too).

In tst_qglobal.cpp and tst_qcollections.cpp change the comment on the
#undef QT_NO_FOREACH to indicate that these actually test the macro.

Task-number: QTBUG-115839
Change-Id: Iecc444eb7d43d7e4d037f6e155abe0e14a00a5d6
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>

6 files changed, 12 insertions, 0 deletions

diff --git a/src/corelib/doc/snippets/code/doc_src_containers.cpp b/src/corelib/doc/snippets/code/doc_src_containers.cpp
index 5bcee95d32..b568462492 100644
--- a/src/corelib/doc/snippets/code/doc_src_containers.cpp
+++ b/src/corelib/doc/snippets/code/doc_src_containers.cpp
@@ -1,6 +1,8 @@
 // Copyright (C) 2016 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
+#undef QT_NO_FOREACH // this file contains unported legacy Q_FOREACH uses
+
 //! [0]
 class Employee
 {
diff --git a/src/corelib/doc/snippets/code/qlogging/qlogging.cpp b/src/corelib/doc/snippets/code/qlogging/qlogging.cpp
index a841829600..e61eb70df3 100644
--- a/src/corelib/doc/snippets/code/qlogging/qlogging.cpp
+++ b/src/corelib/doc/snippets/code/qlogging/qlogging.cpp
@@ -1,6 +1,8 @@
 // Copyright (C) 2016 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
+#undef QT_NO_FOREACH // this file contains unported legacy Q_FOREACH uses
+
 #include <QtGui>
 #include <QtDebug>
 #include <QQmlComponent>
diff --git a/src/corelib/doc/snippets/code/src_corelib_io_qstorageinfo.cpp b/src/corelib/doc/snippets/code/src_corelib_io_qstorageinfo.cpp
index d11368a83d..93029274b1 100644
--- a/src/corelib/doc/snippets/code/src_corelib_io_qstorageinfo.cpp
+++ b/src/corelib/doc/snippets/code/src_corelib_io_qstorageinfo.cpp
@@ -1,6 +1,8 @@
 // Copyright (C) 2014 Ivan Komissarov
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
+#undef QT_NO_FOREACH // this file contains unported legacy Q_FOREACH uses
+
 //! [0]
     QStorageInfo storage(qApp->applicationDirPath());
     if (storage.isValid() && storage.isReady()) {
diff --git a/src/corelib/doc/snippets/code/src_corelib_kernel_qcoreapplication.cpp b/src/corelib/doc/snippets/code/src_corelib_kernel_qcoreapplication.cpp
index 2a3a27e94b..b1198924c8 100644
--- a/src/corelib/doc/snippets/code/src_corelib_kernel_qcoreapplication.cpp
+++ b/src/corelib/doc/snippets/code/src_corelib_kernel_qcoreapplication.cpp
@@ -1,6 +1,8 @@
 // Copyright (C) 2016 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
+#undef QT_NO_FOREACH // this file contains unported legacy Q_FOREACH uses
+
 //! [0]
 QMouseEvent event(QEvent::MouseButtonPress, pos, 0, 0, 0);
 QApplication::sendEvent(mainWindow, &event);
diff --git a/src/corelib/doc/snippets/code/src_corelib_kernel_qmimedata.cpp b/src/corelib/doc/snippets/code/src_corelib_kernel_qmimedata.cpp
index 36cbdefa1c..c6a48c8827 100644
--- a/src/corelib/doc/snippets/code/src_corelib_kernel_qmimedata.cpp
+++ b/src/corelib/doc/snippets/code/src_corelib_kernel_qmimedata.cpp
@@ -1,6 +1,8 @@
 // Copyright (C) 2016 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
+#undef QT_NO_FOREACH // this file contains unported legacy Q_FOREACH uses
+
 //! [0]
 void MyWidget::dragEnterEvent(QDragEnterEvent *event)
 {
diff --git a/src/corelib/doc/snippets/code/src_corelib_kernel_qvariant.cpp b/src/corelib/doc/snippets/code/src_corelib_kernel_qvariant.cpp
index dcae4b6934..7f3f1ce7a0 100644
--- a/src/corelib/doc/snippets/code/src_corelib_kernel_qvariant.cpp
+++ b/src/corelib/doc/snippets/code/src_corelib_kernel_qvariant.cpp
@@ -1,6 +1,8 @@
 // Copyright (C) 2016 The Qt Company Ltd.
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
 
+#undef QT_NO_FOREACH // this file contains unported legacy Q_FOREACH uses
+
 //! [0]
 QDataStream out(...);
 QVariant v(123);                // The variant now contains an int