Bash 3.1 fails to build on AIX

[Nigel Horne]

Since compilation failed bashbug hasn't been installed, so I am having to
guess what is wanted. Let me know if you need any more help.

uname -a: AIX marvin 1 5 005A0E6C4C00
cc version:  C for AIX Compiler, Version 6

CFLAGS=-O2 ./configure works fine

make fails thus:

...
cc -c  -DHAVE_CONFIG_H -DSHELL  -I. -I../.. -I../.. -I../../include
-I../../lib  -O2 tilde.c
rm -f libtilde.a
ar cr libtilde.a tilde.o
test -n "ranlib" && ranlib libtilde.a
make[1]: Leaving directory `/tmp/bash-3.1/lib/tilde'
rm -f bash
cc -L./builtins -L./lib/readline -L./lib/readline -L./lib/glob
-L./lib/tilde  -L./lib/sh    -O2 -o bash shell.o eval.o y.tab.o general.o
make_cmd.o print_cmd.o  dispose_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
array.o arrayfunc.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 -lsh -lreadline -lhistory -lcurses -lglob -ltilde 
lib/intl/libintl.a -liconv  -ldl
ld: 0711-317 ERROR: Undefined symbol: .isnan
ld: 0711-345 Use the -bloadmap or -bnoquiet option to obtain more
information.
make: *** [bash] Error 8

-Nigel