Add a new option --clean_build to validate_failures.py

Add a new option --clean_build to validate_failures.py

This is useful when you have two builds of the same compiler.  One with
your changes.  The other one, a clean build at the same revision.
Instead of using a manifest file, --clean_build will compare the
results it gather from the patched build against those it gathers from
the clean build.

Usage

$ cd /top/of/patched/gcc/bld
$ validate_failures.py --clean_build=clean/bld-gcc
Source directory: /usr/local/google/home/dnovillo/gcc/trunk
Build target:     x86_64-unknown-linux-gnu
Getting actual results from build directory .
        ./x86_64-unknown-linux-gnu/libstdc++-v3/testsuite/libstdc++.sum
        ./x86_64-unknown-linux-gnu/libffi/testsuite/libffi.sum
        ./x86_64-unknown-linux-gnu/libgomp/testsuite/libgomp.sum
        ./x86_64-unknown-linux-gnu/libgo/libgo.sum
        ./x86_64-unknown-linux-gnu/boehm-gc/testsuite/boehm-gc.sum
        ./x86_64-unknown-linux-gnu/libatomic/testsuite/libatomic.sum
        ./x86_64-unknown-linux-gnu/libmudflap/testsuite/libmudflap.sum
        ./x86_64-unknown-linux-gnu/libitm/testsuite/libitm.sum
        ./x86_64-unknown-linux-gnu/libjava/testsuite/libjava.sum
        ./gcc/testsuite/g++/g++.sum
        ./gcc/testsuite/gnat/gnat.sum
        ./gcc/testsuite/ada/acats/acats.sum
        ./gcc/testsuite/gcc/gcc.sum
        ./gcc/testsuite/gfortran/gfortran.sum
        ./gcc/testsuite/obj-c++/obj-c++.sum
        ./gcc/testsuite/go/go.sum
        ./gcc/testsuite/objc/objc.sum
Getting actual results from build directory clean/bld-gcc
        clean/bld-gcc/x86_64-unknown-linux-gnu/libstdc++-v3/testsuite/libstdc++.sum
        clean/bld-gcc/x86_64-unknown-linux-gnu/libffi/testsuite/libffi.sum
        clean/bld-gcc/x86_64-unknown-linux-gnu/libgomp/testsuite/libgomp.sum
        clean/bld-gcc/x86_64-unknown-linux-gnu/libgo/libgo.sum
        clean/bld-gcc/x86_64-unknown-linux-gnu/boehm-gc/testsuite/boehm-gc.sum
        clean/bld-gcc/x86_64-unknown-linux-gnu/libatomic/testsuite/libatomic.sum
        clean/bld-gcc/x86_64-unknown-linux-gnu/libmudflap/testsuite/libmudflap.sum
        clean/bld-gcc/x86_64-unknown-linux-gnu/libitm/testsuite/libitm.sum
        clean/bld-gcc/x86_64-unknown-linux-gnu/libjava/testsuite/libjava.sum
        clean/bld-gcc/gcc/testsuite/g++/g++.sum
        clean/bld-gcc/gcc/testsuite/gnat/gnat.sum
        clean/bld-gcc/gcc/testsuite/ada/acats/acats.sum
        clean/bld-gcc/gcc/testsuite/gcc/gcc.sum
        clean/bld-gcc/gcc/testsuite/gfortran/gfortran.sum
        clean/bld-gcc/gcc/testsuite/obj-c++/obj-c++.sum
        clean/bld-gcc/gcc/testsuite/go/go.sum
        clean/bld-gcc/gcc/testsuite/objc/objc.sum

SUCCESS: No unexpected failures.

2012-11-02  Diego Novillo  <dnovillo@google.com>

	* testsuite-management/validate_failures.py: Add option
	--clean_build to compare test results against another
	build.

From-SVN: r193105