Bug in std.build.LibExeObjStep.setTarget

[joachimschmidt557]

When compiling https://github.com/andrewrk/tetris/tree/27d0d0ec085e1ac0c9cae6092f807a318b15dd44 with the newest zig from master, this error occurs:

/home/joachim/src/zig/build/lib/zig/std/build.zig:1294:17: error: no member named 'arch' in struct 'std.target.Cross'
                .arch = target_arch,
                ^

The code assigns a value to .arch even though std.target.Target.Cross doesn't have this field.

        return self.setTheTarget(Target{
            .Cross = CrossTarget{
                .arch = target_arch,
                .os = target_os,
                .abi = target_abi,
                .cpu_features = target_arch.getBaselineCpuFeatures(),
            },
        });

[andrewrk]

Thanks.

This is obsoleted with the merge of #4550 which landed in 7617610.