libstdc++-2.90.6 fails to build

[Mike Howard <mike@clove.com>]

Environment: RH 5.2 with Cygnus GNU Pro tools for Linux - redhat-980810

make produces:
.....
ake[2]: Leaving directory `/usr/local/vendors/cygnus/libstdc++/libstdc++-2.90.6
/libio'
Making all in src
make[2]: Entering directory `/usr/local/vendors/cygnus/libstdc++/libstdc++-2.90
.6/src'
/bin/sh ../libtool --mode=compile c++ -DHAVE_CONFIG_H -I. -I. -I.. -nostdinc++ 
-I.. -I../stl -I../libio     -g -D_GNU_SOURCE -fno-implicit-templates  -c 
../src/limitsMEMBERS.cc
rm -f .libs/limitsMEMBERS.lo
c++ -DHAVE_CONFIG_H -I. -I. -I.. -nostdinc++ -I.. -I../stl -I../libio -g 
-D_GNU_SOURCE -fno-implicit-templates -c  -fPIC -DPIC ../src/limitsMEMBERS.cc
c++: ../src/limitsMEMBERS.cc: No such file or directory
c++: No input files
make[2]: *** [../src/limitsMEMBERS.lo] Error 1
make[2]: Leaving directory `/usr/local/vendors/cygnus/libstdc++/libstdc++-2.90.
6/src'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/usr/local/vendors/cygnus/libstdc++/libstdc++-2.90.
6'
make: *** [all-recursive-am] Error 2

I poked around in the CVS tree looking at the Makefiles in (buildroot) and 
buildroot/src, but am stumped.  I can't figure out how limitsMEMBERS.cc is 
constructed - looks like it went in in buildroot/Makefile.in 1.7 & 1.8 and 
disappeared in 1.9.  Is this possible or am I (a) stupid or (b) overwhelmed by 
the complexity of libtool and friends?

BTW - I'd like to help if I can find a little time.  What is an appropriate 
piece of code to whittle on?

thanks in adv,
-- 
Mike Howard <mike@clove.com>