./libtool[1086]: eval: syntax error at line 1: `|' unexpected

[Jeffrey Walton]

I'm trying to build libidn2 on Solaris 11.3 x86_64. Its part of a Git
upgrade because Oracle charges for updates and we don't have a support
contract.

The build fails with the following:

gmake[2]: Entering directory `/export/home/build/libidn2-0.16'
/bin/sh ./libtool  --tag=CC   --mode=link gcc -std=gnu99
-fvisibility=hidden -m64 -version-info 1:4:1 -no-undefined
-export-symbols-regex '^idn2_.*|_idn2_punycode_..code'  -o libidn2.la
-rpath /usr/local/lib64 idna.lo lookup.lo register.lo bidi.lo
version.lo error.lo punycode.lo free.lo data.lo tr46map.lo tables.lo
context.lo -L/usr/local/lib64 -liconv -R/usr/local/lib64
-L/usr/local/lib64 -lunistring -L/usr/local/lib64 -liconv -ldl
-lpthread -R/usr/local/lib64 lib/libgnu.la -ldl -lpthread
libtool: link: /bin/nm -p  .libs/idna.o .libs/lookup.o
.libs/register.o .libs/bidi.o .libs/version.o .libs/error.o
.libs/punycode.o .libs/free.o .libs/data.o .libs/tr46map.o
.libs/tables.o .libs/context.o   lib/.libs/libgnu.a |  | /bin/gsed
's/.* //' | sort | uniq > .libs/libidn2.exp
./libtool[1086]: eval: syntax error at line 1: `|' unexpected
gmake[2]: *** [libidn2.la] Error 3

If I am parsing things correctly, the "unexpected |" is due to a
missing command. Solaris is very Posixy, and I'm not sure which
command may be running afoul.

My questions are:

  1. Is a command missing?
  2. If so, which command is missing?
  3. How do I fix the issue?

Thanks in advance.