For arm-none-linux-gnueabi ld/configure.host (from CVS HEAD as of 23 March 2010)
executes the following sequence of commands to set HOSTING_CRT0 to the correct
value:

HOSTING_CRT0='-p -dynamic-linker `${CC} --help --verbose 2>&1 | egrep "ld[^
]*\.so" | sed -e "s,.*-dynamic-linker[ 	][ 	]*\(.*/ld[^ ]*\.so..\).*,\1,"`
`${CC} --print-file-name=crt1.o` `${CC} --print-file-name=crti.o` `if [ -f
../gcc/crtbegin.o ]; then echo ../gcc/crtbegin.o; else ${CC}
--print-file-name=crtbegin.o; fi`'
HOSTING_CRT0=`echo "$HOSTING_CRT0" | sed -e "s,ld\[^ \]\*,ld-linux,g"`

When executed in bash HOSTING_CRT0 is now equal to:
-p -dynamic-linker `${CC} --help --verbose 2>&1 | egrep "ld-linux\.so" | sed -e
"s,.*-dynamic-linker[ 	][ 	]*\(.*/ld-linux\.so..\).*,\1,"` `${CC}
--print-file-name=crt1.o` `${CC} --print-file-name=crti.o` `if [ -f
../gcc/crtbegin.o ]; then echo ../gcc/crtbegin.o; else ${CC}
--print-file-name=crtbegin.o; fi`

But with dash it is equal to:
-p -dynamic-linker `${CC} --help --verbose 2>&1 | egrep "ld-linux\.so" | sed -e
"s,.*-dynamic-linker[ 	][ 	]*\(.*/ld-linux\.so..\).*,^A,"` `${CC}
--print-file-name=crt1.o` `${CC} --print-file-name=crti.o` `if [ -f
../gcc/crtbegin.o ]; then echo ../gcc/crtbegin.o; else ${CC}
--print-file-name=crtbegin.o; fi`

(Where ^A is the character with value 1).

This then causes many ld tests to fail if /bin/sh is linked to dash instead of
bash (as is the case for Ubuntu).

My reading of POSIX says that the output of:
echo "\1" 
is implementation defined and so dash's behaviour is acceptable, (as is in this
case bash's).

I believe this issue also affects other targets including x86_64 and mips.

A workaround for these issues is to make the first "exec sh ..." in
get_link_files in ld/testsuite/config/default.exp be "exec bash ..." instead.

ld tests that fail if sh is dash instead of bash are:
Running /home/mgretton/binutils/src/ld/testsuite/ld-bootstrap/bootstrap.exp ...
FAIL: bootstrap
FAIL: bootstrap with strip
FAIL: bootstrap with --traditional-format
FAIL: bootstrap with --no-keep-memory
FAIL: bootstrap with --relax
Running /home/mgretton/binutils/src/ld/testsuite/ld-cdtest/cdtest.exp ...
FAIL: cdtest
FAIL: cdtest with -Ur
Running /home/mgretton/binutils/src/ld/testsuite/ld-elf/dwarf.exp ...
FAIL: Run with libdwarf1.so first
FAIL: Run with libdwarf1.so last
Running /home/mgretton/binutils/src/ld/testsuite/ld-elf/elf.exp ...
FAIL: preinit array
FAIL: init array
FAIL: fini array
Running /home/mgretton/binutils/src/ld/testsuite/ld-elf/shared.exp ...
FAIL: Run normal with libfoo.so
FAIL: Run protected with libfoo.so
FAIL: Run hidden with libfoo.so
FAIL: Run normal with versioned libfoo.so
FAIL: Run warn with versioned libfoo.so
FAIL: Run protected with versioned libfoo.so
FAIL: Run hidden with versioned libfoo.so
FAIL: Run normal libbar.so with libfoo.so
FAIL: Run protected libbar.so with libfoo.so
FAIL: Run hidden libbar.so with libfoo.so
FAIL: Run normal libbar.so with versioned libfoo.so
FAIL: Run protected libbar.so with versioned libfoo.so
FAIL: Run hidden libbar.so with versioned libfoo.so
FAIL: Run dl1a with --dynamic-list=dl1.list and dlopen on libdl1.so
FAIL: Run dl1b with --dynamic-list-data and dlopen on libdl1.so
FAIL: Run with libdl2a.so
FAIL: Run with libdl2b.so
FAIL: Run with libdl2c.so
FAIL: Run with libdl4a.so
FAIL: Run with libdl4b.so
FAIL: Run with libdl4c.so
FAIL: Run with libdl4d.so
FAIL: Run with libdl4e.so
FAIL: Run with libdl4f.so
FAIL: Run dl6a1 with --dynamic-list-data and dlopen on libdl6a.so
FAIL: Run dl6a2 with -Bsymbolic-functions and dlopen on libdl6a.so
FAIL: Run dl6a3 with -Bsymbolic and dlopen on libdl6a.so
FAIL: Run dl6a4 with -Bsymbolic --dynamic-list-data and dlopen on libdl6a.so
FAIL: Run dl6a5 with -Bsymbolic-functions --dynamic-list-cpp-new and dlopen on
libdl6a.so
FAIL: Run dl6a6 with --dynamic-list-cpp-new -Bsymbolic-functions and dlopen on
libdl6a.so
FAIL: Run dl6a7 with --dynamic-list-data -Bsymbolic and dlopen on libdl6a.so
FAIL: Run dl6b1 with --dynamic-list-data and dlopen on libdl6b.so
FAIL: Run dl6b2 with dlopen on libdl6b.so
FAIL: Run dl6c1 with --dynamic-list-data and dlopen on libdl6c.so
FAIL: Run dl6d1 with --dynamic-list-data and dlopen on libdl6d.so
FAIL: Run with libdata1.so
FAIL: Run with libfunc1.so comm1.o
FAIL: Run with comm1.o libfunc1.so
FAIL: Run with pr11138-2.c libpr11138-1.so
FAIL: Run with libpr11138-1.so pr11138-2.c