Further enhance the check for needed tools:
- update the tool_pattern to use ' || ' as a pattern separator
- which allows using | in regexp
- add checks for cut and xargs
- manually check for grep and sed because they are needed when checking for tools
- print why a test failed, with each tested tool and regexp
- move tools checks before options parsing
- apply conttibutions before computing the version string
- inform user to run make && make install

/trunk/configure | 173 111 62 0 ++++++++++++++++++++++++++++++++++++++++----------------------
1 file changed, 111 insertions(+), 62 deletions(-)

 diff -durN gcc-4.2.1.orig/libstdc++-v3/configure gcc-4.2.1/libstdc++-v3/configure

 --- gcc-4.2.1.orig/libstdc++-v3/configure	2007-08-03 20:30:21.000000000 +0200

 +++ gcc-4.2.1/libstdc++-v3/configure	2007-08-03 20:33:56.000000000 +0200

 @@ -7514,6 +7514,9 @@

  cat >>conftest.$ac_ext <<_ACEOF

  /* end confdefs.h.  */

  #include <complex.h>

 +#ifdef __UCLIBC__

 +#error ugly hack to make sure configure test fails here for cross until uClibc supports the complex funcs

 +#endif

  int

  main ()

  {