enhance the test to check that ranged-for with non-reference cannot modify the SIMD object
enhance the test to check that ranged-for with non-reference cannot modify the SIMD object

VcDevel/Vc,chr-engwer/Vc,VcDevel/Vc,VcDevel/Vc,VcDevel/Vc,chr-engwer/Vc,chr-engwer/Vc