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

 Conflicts:
	src/corelib/tools/qstring.cpp

Change-Id: I81dbf90fc936c9bf08197baefa071117bddb1c63

2 files changed, 15 insertions, 2 deletions

diff --git a/qmake/doc/src/qmake-manual.qdoc b/qmake/doc/src/qmake-manual.qdoc
index 3119a440d4..27f45089d1 100644
--- a/qmake/doc/src/qmake-manual.qdoc
+++ b/qmake/doc/src/qmake-manual.qdoc
@@ -974,6 +974,9 @@
             the compiler does not support C++17, or can't select the C++ standard.
             By default, support is disabled.
     \row    \li c++17 \li Same as c++1z.
+    \row    \li c++2a \li C++2a support is enabled. This option has no effect if
+            the compiler does not support C++2a, or can't select the C++ standard.
+            By default, support is disabled.
     \row    \li strict_c++ \li Disables support for C++ compiler extensions.
             By default, they are enabled.
     \row    \li depend_includepath \li Appending the value of INCLUDEPATH to
@@ -1160,6 +1163,10 @@
 
     \snippet code/doc_src_qmake-manual.pro 30
 
+    \note The list of supported characters can depend on
+    the used build tool. In particular, parentheses do not
+    work with \c{make}.
+
     \target DISTFILES
     \section1 DISTFILES
 
diff --git a/qmake/generators/makefiledeps.cpp b/qmake/generators/makefiledeps.cpp
index decc1d980c..1aab1987d2 100644
--- a/qmake/generators/makefiledeps.cpp
+++ b/qmake/generators/makefiledeps.cpp
@@ -837,7 +837,9 @@ bool QMakeSourceFileInfo::findDeps(SourceFile *file)
         if(inc) {
             if(!includes)
                 includes = new SourceFiles;
-            SourceFile *dep = includes->lookupFile(inc);
+            /* QTBUG-72383: Local includes "foo.h" must first be resolved relative to the
+             * sourceDir, only global includes <bar.h> are unique. */
+            SourceFile *dep = try_local ? nullptr : includes->lookupFile(inc);
             if(!dep) {
                 bool exists = false;
                 QMakeLocalFileName lfn(inc);
@@ -876,7 +878,11 @@ bool QMakeSourceFileInfo::findDeps(SourceFile *file)
                         dep->file = lfn;
                         dep->type = QMakeSourceFileInfo::TYPE_C;
                         files->addFile(dep);
-                        includes->addFile(dep, inc, false);
+                        /* QTBUG-72383: Local includes "foo.h" are keyed by the resolved
+                         * path (stored in dep itself), only global includes <bar.h> are
+                         * unique keys immediately. */
+                        const char *key = try_local ? nullptr : inc;
+                        includes->addFile(dep, key, false);
                     }
                     dep->exists = exists;
                 }