linker not configured to use sysroot

[mencaraglia francesco]

I am using Linux/Kubuntu OS. I have recently updated to 12.04 and I am
getting problem with gcc. Using the simple program

#include <stdio.h>
main()
{fprintf(stdout,"hello world\n");
return 0;
}

the compilation (gcc -c test.c) is ok but when I try to link (gcc
test.o) I get
/usr/local/bin/ld: this linker was not configured to use sysroots
collect2: ld returned 1 exit status

the loader ld is version 2.22 (as obtained using ld --version) and gcc
is the 4.6 release (gcc -v ) more details below.

Before the update everything was running smoothly so I thing that
during the update I have done something wrong. Ay suggestion welcome


Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/i686-linux-gnu/4.6/lto-wrapper
Target: i686-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro
4.6.3-1ubuntu5' --with-bugurl=file:///usr/share/doc/gcc-4.6/README.Bugs
--enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --program-
suffix=-4.6 --enable-shared --enable-linker-build-id --with-system-zlib
--libexecdir=/usr/lib --without-included-gettext --enable-threads=posix
--with-gxx-include-dir=/usr/include/c++/4.6 --libdir=/usr/lib --enable-
nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --
enable-libstdcxx-time=yes --enable-gnu-unique-object --enable-plugin --
enable-objc-gc --enable-targets=all --disable-werror --with-
arch-32=i686 --with-tune=generic --enable-checking=release --
build=i686-linux-gnu --host=i686-linux-gnu --target=i686-linux-gnu
Thread model: posix
gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5)