wkGetGlyphsForCharacters() sometimes crashes with UVS

• Component: Platform
• Status: NEW ---

[Kenichi Ishibashi]

For example: http://build.chromium.org/p/chromium.webkit/builders/Webkit%20Mac10.6%20(CG)/builds/3463/steps/webkit_tests/logs/stdio

2011-12-15 15:29:09,735 40363 single_test_runner.py:194 DEBUG worker/6 Stacktrace for fast/text/unicode-variation-selector.html:
	0   DumpRenderTree                      0x47e33a5a 0x0 + 1206073946
	1   DumpRenderTree                      0x47e54cc1 0x0 + 1206209729
	2   libSystem.B.dylib                   0x9603e05b _sigtramp + 43
	3   ???                                 0xffffffff 0x0 + 4294967295
	4   libFontParser.dylib                 0x93fa126e TFormat14UVSTable::Map(int, int, unsigned short*) const + 100
	5   libFontParser.dylib                 0x93fa8394 unsigned int TFormat12UTF16cmapTable::MapT<true>(unsigned short const*, unsigned short*, unsigned int&) const + 404
	6   libFontParser.dylib                 0x93f6ea23 TcmapUnicodeTable::Map(unsigned short const*, unsigned short*, unsigned int&) const + 793
	7   libFontParser.dylib                 0x93f6db5d TSFNTFont::GetGlyphsPerCharacters(unsigned short const*, unsigned short*, unsigned int&, bool) const + 69
	8   libFontParser.dylib                 0x93f6da7f FPFontGetGlyphsForUnichars + 544
 :
 :

This looks the same stacktrace as https://bugs.webkit.org/show_bug.cgi?id=50999#c3. As mentioned in the comment, valid arguments were passed here.

[Kenichi Ishibashi]

Hi mitz,

Do you have any ideas about this crash? You reviewed https://bugs.webkit.org/show_bug.cgi?id=46973 which added the function.