diff --git a/src/corelib/kernel/qcoreapplication.cpp b/src/corelib/kernel/qcoreapplication.cpp
index f3934210797..09b7c4fce31 100644
--- a/src/corelib/kernel/qcoreapplication.cpp
+++ b/src/corelib/kernel/qcoreapplication.cpp
@@ -2449,6 +2449,11 @@ QString QCoreApplication::applicationFilePath()
         return d->cachedApplicationFilePath;
 
     QString absPath = qAppFileName();
+    if (Q_LIKELY(!absPath.isEmpty())) {   // Darwin, FreeBSD, Linux, Windows
+        // the OS has canonicalized for us
+        return d->cachedApplicationFilePath = std::move(absPath);
+    }
+
     if (absPath.isEmpty() && !arguments().isEmpty()) {
         QString argv0 = QFile::decodeName(arguments().at(0).toLocal8Bit());
 
diff --git a/src/corelib/kernel/qcoreapplication_mac.cpp b/src/corelib/kernel/qcoreapplication_mac.cpp
index af047fe8cde..982672caa57 100644
--- a/src/corelib/kernel/qcoreapplication_mac.cpp
+++ b/src/corelib/kernel/qcoreapplication_mac.cpp
@@ -12,6 +12,7 @@ QT_BEGIN_NAMESPACE
  *****************************************************************************/
 QString qAppFileName()
 {
+    // QCoreApplication::applicationFilePath() expects a canonical path
     static QString appFileName;
     if (appFileName.isEmpty()) {
         QCFType<CFURLRef> bundleURL(CFBundleCopyExecutableURL(CFBundleGetMainBundle()));
diff --git a/src/corelib/kernel/qcoreapplication_win.cpp b/src/corelib/kernel/qcoreapplication_win.cpp
index 9011e3fe9e6..2cdf0d57d46 100644
--- a/src/corelib/kernel/qcoreapplication_win.cpp
+++ b/src/corelib/kernel/qcoreapplication_win.cpp
@@ -5,6 +5,7 @@
 #include "qcoreapplication.h"
 #include "qcoreapplication_p.h"
 #include "qstringlist.h"
+#include "qdir.h"
 #include "qfileinfo.h"
 #ifndef QT_NO_QOBJECT
 #include "qmutex.h"
@@ -52,7 +53,10 @@ QString qAppFileName()                // get application file name
         v = GetModuleFileName(hInstance, space.data(), DWORD(space.size()));
     } while (Q_UNLIKELY(v >= size));
 
-    return QString::fromWCharArray(space.data(), v);
+    // QCoreApplication::applicationFilePath() expects a canonical path with
+    // Qt-style separators
+    QStringView nativePath(space.data(), v);
+    return QDir::fromNativeSeparators(nativePath.toString());
 }
 
 QString QCoreApplicationPrivate::appName() const