workaround issue where casing diff overflows signed short

there are two such codepoints were added in the Unicode 5.1:
  U+1D79  LATIN SMALL LETTER INSULAR G
  U+A77D  LATIN CAPITAL LETTER INSULAR G
two more of them were added in the Unicode 6.0:
  U+0265  LATIN SMALL LETTER TURNED H
  U+A78D  LATIN CAPITAL LETTER TURNED H
and two more were added in the Unicode 6.1:
  U+0266  LATIN SMALL LETTER H WITH HOOK
  U+A7AA  LATIN CAPITAL LETTER H WITH HOOK

we map them like special cases with length == 1
(note: all are in BMP which is checked explicitly in the generator)

Change-Id: I8a34164eb3ee2e575b7799cc12d4b96ad5bcd9c6
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/src/corelib/tools/qstring.cpp b/src/corelib/tools/qstring.cpp
index 65b52f3229..39747aa3e9 100644
--- a/src/corelib/tools/qstring.cpp
+++ b/src/corelib/tools/qstring.cpp
@@ -5263,7 +5263,20 @@ QString QString::toCaseFolded() const
                     prop = qGetProp(*p);
                 }
                 if (prop->caseFoldSpecial) {
+                    const ushort *specialCase = specialCaseMap + prop->caseFoldDiff;
+                    ushort length = *specialCase++;
+#if 0
+                    int pos = pp - s.d->data;
+                    s.resize(s.d->size + length - 1);
+                    pp = s.d->data + pos;
+                    while (length--)
+                        *pp++ = *specialCase++;
+#else
                     //### we currently don't support full case foldings
+                    Q_ASSERT(length == 1);
+                    Q_UNUSED(length)
+                    *pp++ = *specialCase;
+#endif
                 } else {
                     *pp++ = *p + prop->caseFoldDiff;
                 }