lilypond-book runs xelatex linked against non-system libraries

[Joe Neeman]

Consider the following lilypond-book output (version 2.14.2):
lilypond-book --pdf --latex-program=xelatex -o out miriam.lytex
lilypond-book (GNU LilyPond) 2.14.2
Reading miriam.lytex...
Running xelatex...xelatex: /home/jneeman/lilypond/usr/lib/libstdc++.so.6:
no version information available (required by xelatex)
...
xelatex: relocation error: xelatex: symbol
_ZNSt8__detail15_List_node_base7_M_hookEPS0_, version GLIBCXX_3.4.15 not
defined in file libstdc++.so.6 with link time reference
command failed: xelatex /tmp/tmpPBb_rA.tex
Child returned 127

It looks like lilypond-book is running xelatex in a modified environment
(eg. with LD_LIBRARY_PATH set). Since xelatex is not packaged with
lilypond, it should be linked against whatever libraries are present on the
system, not the libraries that are packaged with lilypond.

Joe