QCollator: port compare(ptr, n, ptr, n) to qsizetype

While the function is inline, the class is exported wholesale, so the
function forms part of the ABI on Windows (but not Unix), so we must
overload, can't replace.

To avoid ambiguities where users pass different integer types as the
lengths of the LHS and RHS strings, QT_REMOVED_SINCE the old overload.

Since the removed function has an inline definition, it suffices to
just include the header into the corresponding QT_REMOVED_SINCE
section of the removed_api.cpp file, to elegantly solve the BiC
problem only for those platforms (MSVC) where it matters.

Pick-to: 6.4
Task-number: QTBUG-103531
Change-Id: I74d446f08fcd6247a2ec44575b8afef8d014c3b5
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

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"

src/corelib/text/qcollator.cpp

@@ -320,7 +320,7 @@ 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
 
@@ -329,6 +329,9 @@ 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}.
 */
 
 /*!

src/corelib/text/qcollator.h

@@ -67,8 +67,12 @@ public:
 
     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; }