##In case , you ever build your bash shell and would like to re-build again , please do "make clean" and then re-configure again.
lfs@Microknoppix:/mnt/lfs/sources/bash-4.3.30$ make
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* *
* GNU bash, version 4.3.30(3)-release (x86_64-unknown-linux-gnu)
* *
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rm -f bash
gcc -L./builtins -L./lib/readline -L./lib/readline -L./lib/glob -L./lib/tilde -L./lib/sh -L./lib/termcap -rdynamic -g -O2 -o bash
shell.o eval.o y.tab.o general.o make_cmd.o print_cmd.o d
ispose_cmd.o execute_cmd.o variables.o copy_cmd.o error.o expr.o flags.o jobs.o subst.o hashcmd.o hashlib.o mailcheck.o trap.o input.o
unwind_prot.o pathexp.o sig.o test.o version.o alias.o a
rray.o arrayfunc.o assoc.o braces.o bracecomp.o bashhist.o bashline.o list.o stringlib.o locale.o findcmd.o redir.o pcomplete.o
pcomplib.o syntax.o xmalloc.o -lbuiltins -lglob -lsh -lreadline -lhistory ./lib/termcap/libtermcap.a -ltilde -ldl
/mnt/lfs/tools/bin/../lib/gcc/x86_64-unknown-linux-gnu/4.9.2/../../../../x86_64-unknown-linux-gnu/bin/ld: i386 architecture of input
file `./lib/sh/libsh.a(shmatch.o)' is incompatible with i386:x86-64 output
/mnt/lfs/tools/bin/../lib/gcc/x86_64-unknown-linux-gnu/4.9.2/../../../../x86_64-unknown-linux-gnu/bin/ld: i386 architecture of input
file `./lib/sh/libsh.a(winsize.o)' is incompatible with i386:x86-64 output
/mnt/lfs/tools/bin/../lib/gcc/x86_64-unknown-linux-gnu/4.9.2/../../../../x86_64-unknown-linux-gnu/bin/ld: i386 architecture of input
file `./lib/sh/libsh.a(unicode.o)' is incompatible with i386:x86-64 output
/mnt/lfs/tools/bin/../lib/gcc/x86_64-unknown-linux-gnu/4.9.2/../../../../x86_64-unknown-linux-gnu/bin/ld: i386 architecture of input
file `./lib/sh/libsh.a(shmbchar.o)' is incompatible with i386:x86-64 output
./lib/sh/libsh.a(shmatch.o): In function `sh_regmatch':
/mnt/lfs/sources/bash-4.3.30/lib/sh/shmatch.c:111: undefined reference to `sh_xfree'
/mnt/lfs/sources/bash-4.3.30/lib/sh/shmatch.c:112: undefined reference to `sh_xfree'
collect2: error: ld returned 1 exit status
make: *** [bash] Error 1
==> Fix by change "make" to "make clean" and reconfigure again.
#./configure --prefix=/tools
#make
#make install
