Don't force building target GMP and MPFR when a native gdb is built. Rather,
add a config knob to configure the native gdb to use or not to use GMP and
MPFR; _this_config_knob_ will force building the target GMP and MPFR only if
turned on.

/trunk/scripts/build/debug/300-gdb.sh | 2 1 1 0 +-
/trunk/config/debug/gdb.in | 21 19 2 0 +++++++++++++++++++--
2 files changed, 20 insertions(+), 3 deletions(-)

 #!/bin/bash

 # This scripts extracts a crosstool-NG configuration from the log file

 # of a toolchain build with crosstool-NG.

 # Usage: cat <logfile> |$0

 awk '

 BEGIN {

   dump = 0;

 }

 $0~/Dumping crosstool-NG configuration: done in.+s$/ {

   dump = 0;

 }

 dump == 1 { $1 = "" }

 dump == 1

 $0~/Dumping crosstool-NG configuration$/ {

   dump = 1;

 }

 ' |cut -d ' ' -f 2-