FYI, /bin/sh bug on opensolaris 5.11

[Jim Meyering]

FYI,

This script segfaults on opensolaris 5.11 snv_134 i86pc:

#!/bin/sh
rm -f x && \
echo y | sed -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, \
-e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, \
-e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, \
-e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, | cat

    $ sh -x ~/sh-abuse
    + rm -f x
    + echo y
    Segmentation Fault (core dumped)
    [Exit 139 (SIGSEGV)]

If I tweak it slightly, say by changing "x" to "xxx", it does this:

    + rm -f xxx
    + echo y
    + sed -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e 
s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e 
s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e 
s,,, -e s,,, -e s,,, -e s,,,
    + cat

and hangs, waiting for input from *me*.
If I type ^D, it terminates with no further output.

If instead, I change the "rm -f x" to something shorter,
like "echo", it does this:

    + echo

    + echo y
    + cat

If I remove one of the "-e s,,," pairs, it actually runs sed
and diagnoses a problem:

    + rm -f xxx
    + echo y
    + sed -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e 
s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e 
s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e s,,, -e 
s,,, -e s,,, -e s,,,
    sed: -e expression #31, char 0: no previous regular expression
    + cat

All of this to say you probably don't want to use
that version of /bin/sh on solaris 5.11.

This is relevant because a default coreutils build
uses /bin/sh to create files like gnulib's lib/stdlib.h
using sed commands with many -e arg pairs like the above.
For me, "make" hung with a pipeline like the above waiting
for tty input. Using "make SHELL=bash" worked around it.