diff --git a/src/corelib/compat/removed_api.cpp b/src/corelib/compat/removed_api.cpp
index d56ea9f43af..c2cff280011 100644
--- a/src/corelib/compat/removed_api.cpp
+++ b/src/corelib/compat/removed_api.cpp
@@ -169,6 +169,8 @@ QCalendar::QCalendar(QStringView name)
 QCalendar::QCalendar(QLatin1StringView name)
     : QCalendar(QAnyStringView{name}) {}
 
+#include "qcollator.h" // inline function compare(ptr, n, ptr, n) (for MSVC)
+
 #if QT_CONFIG(future)
 
 #include "qfutureinterface.h"
diff --git a/src/corelib/text/qcollator.cpp b/src/corelib/text/qcollator.cpp
index 4db6950f762..34c14a89b4e 100644
--- a/src/corelib/text/qcollator.cpp
+++ b/src/corelib/text/qcollator.cpp
@@ -318,7 +318,7 @@ bool QCollator::ignorePunctuation() const
 */
 
 /*!
-    \fn int QCollator::compare(const QChar *s1, int len1, const QChar *s2, int len2) const
+    \fn int QCollator::compare(const QChar *s1, qsizetype len1, const QChar *s2, qsizetype len2) const
     \overload
     \since 5.2
 
@@ -327,6 +327,9 @@ bool QCollator::ignorePunctuation() const
 
     Returns an integer less than, equal to, or greater than zero depending on
     whether \a s1 sorts before, with or after \a s2.
+
+    \note In Qt versions prior to 6.4, the length arguments were of type
+    \c{int}, not \c{qsizetype}.
 */
 #endif // QT_STRINGVIEW_LEVEL < 2
 
diff --git a/src/corelib/text/qcollator.h b/src/corelib/text/qcollator.h
index 315ce43e9b5..3a9824448b7 100644
--- a/src/corelib/text/qcollator.h
+++ b/src/corelib/text/qcollator.h
@@ -68,8 +68,12 @@ public:
 #if QT_STRINGVIEW_LEVEL < 2
     int compare(const QString &s1, const QString &s2) const
     { return compare(QStringView(s1), QStringView(s2)); }
+#if QT_CORE_REMOVED_SINCE(6, 4) && QT_POINTER_SIZE != 4
     int compare(const QChar *s1, int len1, const QChar *s2, int len2) const
     { return compare(QStringView(s1, len1), QStringView(s2, len2)); }
+#endif
+    int compare(const QChar *s1, qsizetype len1, const QChar *s2, qsizetype len2) const
+    { return compare(QStringView(s1, len1), QStringView(s2, len2)); }
 
     bool operator()(const QString &s1, const QString &s2) const
     { return compare(s1, s2) < 0; }