# unicode-math and amsmath environments

I'd like to use unicode-math but I've run into some problems. The following mwe, compiles without problems. The aligned environment is used

\documentclass{article}
\usepackage{amsmath}
\usepackage{unicode-math}
\setmathfont{XITS Math}
\usepackage{xltxtra}

\begin{document}

$$α = \beta^2_i + β^2_i$$

\begin{align}
a &= b\\
b &= c
\end{align}

\end{document}


but if I add the following code (using cases environment - defined in amsmath) then I get a segmentation fault

$$\begin{cases} a &= b\\ b &= c \end{cases}$$


What I want to ask is if the two packages can be used together (so this is a bug) or if I am going to encounter more problems like this one.

The output of the compilation is this one and here is the log file.

ps. I know that it is easy to emulate the cases environment.

ps2. Although it must be obvious, I am using xelatex.

UPDATE I am using TexLive 2010 64bit on Linux

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Are you using the 64bit version of XeTeX? –  Caramdir Feb 2 '11 at 20:19
At present your example does not compile: it does not load amsmath or unicode-math. Even if I do, I don't get any α or β in the output, so simply adding them is not enough. –  Joseph Wright Feb 2 '11 at 20:20
@Joseph: When loading unicode-math, you also need to specify a font (but I agree, the example code is incomplete). –  Caramdir Feb 2 '11 at 20:21
Your MWE cannot be compiled proberly for me, since amsmath is missing, and unicode-math is missing. Please put the real MWE here. –  Leo Liu Feb 2 '11 at 20:21
I've had problems with unicode-math, 64 bit xelatex on linux, and scaleable delimiters so this may well be the same problem. My workaround was to install the 32bit version of TeXLive and use that instead (whereupon it all worked fine). –  Andrew Stacey Feb 2 '11 at 22:02

Andrew’s hint is correct: the Linux 64-bit version of XeTeX has a regression, see the bug tracker. You can either:

1. Wait for the bug fix to propagate to downstream TeX Live (won’t probably happen until TeX Live 2011), or
2. Install the 32-bit architecture. TeX Live supports multiple architectures on Linux:

tlmgr platform add i386-linux


After that you can place a symlink to the 32-bit xetex and xelatex executables in a directory which comes early in your PATH (e.g. ~/bin). This way, you can continue using the other 64-bit binaries.

3. Or use LuaTeX instead, which doesn’t have that bug.
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Theoretically, you could also compile XeTeX yourself with that patch applied (though using 32bit XeTeX or LuaTeX is the easier solution). –  Caramdir Feb 2 '11 at 23:44
@ Philipp : Thank you very much! I'll try the 32bit version. –  pmav99 Feb 2 '11 at 23:53