Finally used the discovered paths from ./configure in scripts/crosstool-NG.sh:
- fix Makefile to really, really not used built-in rules and variables
- have scripts/crosstool-NG.sh generated from scripts/crosstool-NG.sh.in
- create a bin-overide directory ( in ${CT_WORK_DIR}/bin ) that contains shell wrappers to the actual discovered tools

/trunk/scripts/crosstool-NG.sh.in | 27 23 4 0 +++++++++++++++++++++---
/trunk/Makefile.in | 50 48 2 0 +++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 71 insertions(+), 6 deletions(-)

 source config/global.in

 source config/target.in

 source config/toolchain.in

 source config/kernel.in

 source config/gmp_mpfr.in

 source config/binutils.in

 source config/cc.in

 source config/libc.in

 source config/tools.in

 source config/debug.in