[ft] Glyph 0xBB does not load from TTF-FreeFont FreeSerif.ttf since 6.12.2

[Volker Schatz]

    Hello,

I am using freetype in a personal fork of the text/graphical links browser and
have the following issue since a few months ago.

As of version 6.12.2, a single glyph from FreeSerif.ttf (from
http://www.nongnu.org/freefont/) cannot be loaded any more, namely code point
0xBB (">>", guillemotright).

This small program demonstrates the problem:
http://volkerschatz.com/tmp/freetype2-0xBB.c
With my current freetype version, 6.12.3, it fails, but when LD_PRELOADing
version 6.12.1, it succeeds.  As far as I can tell, the problem occurs only
with FreeSerif.ttf and only with glyph 0xBB.

The error code is 0x15, "invalid composite glyph".  As far as I can see with
fontforge, this looks like a composite glyph, as each of the ">" angles has a
caption "guilsinglright" attached.  But the same goes for 0xAB (guillemotleft),
which loads OK with the current freetype library.  I do not have the tools to
investigate the font file further.

Should I file a bug report for freetype, am I doing something wrong, or is it a
bug in FreeSerif.ttf?

Thanks in advance for any help.

Volker


PS: I am using Arch Linux.  System details:
$ uname -a
Linux octopus 4.4.10-1-lts #1 SMP Wed May 11 21:03:02 CEST 2016 x86_64 GNU/Linux
$ ldd /usr/lib/libfreetype.so.6.12.3 
    linux-vdso.so.1 (0x00007ffd3386b000)
    libz.so.1 => /usr/lib/libz.so.1 (0x00007f643b189000)
    libbz2.so.1.0 => /usr/lib/libbz2.so.1.0 (0x00007f643af79000)
    libpng16.so.16 => /usr/lib/libpng16.so.16 (0x00007f643ad41000)
    libharfbuzz.so.0 => /usr/lib/libharfbuzz.so.0 (0x00007f643aac1000)
    libc.so.6 => /usr/lib/libc.so.6 (0x00007f643a719000)
    libm.so.6 => /usr/lib/libm.so.6 (0x00007f643a411000)
    libglib-2.0.so.0 => /usr/lib/libglib-2.0.so.0 (0x00007f643a101000)
    libgraphite2.so.3 => /usr/lib/libgraphite2.so.3 (0x00007f6439ed1000)
    /usr/lib64/ld-linux-x86-64.so.2 (0x000055d7c14f3000)
    libpcre.so.1 => /usr/lib/libpcre.so.1 (0x00007f6439c61000)
    libpthread.so.0 => /usr/lib/libpthread.so.0 (0x00007f6439a41000)