tree bbffe4baa04dd4fd15169f1da2fe2a83d696d891
parent de2791648512e8bf2f898b2af9ae1c56c03f2931
author rosica <rosica@google.com> 1549472155 -0800
committer Copybara-Service <copybara-worker@google.com> 1549472170 -0800

Remove fail("Unreachable") from features' and action_configs' declaration statements

If toolchain A and B need feature f, but toolchain C doesn't, the generated declaration statement for feature f would be:
if ctx.attr.cpu == 'A.cpu':
   f = feature(...)
elif ctx.attr.cpu == "B.cpu" and ctx.attr.compiler == "B.compiler":
   f = feature(...)
else:
   fail("Unreachable")

This will break the rule implementation in the case of toolchain C because it will reach the  fail("Unreachable") although it doesn't need to declare feature f

This cl fixes that

Issue #5380

PiperOrigin-RevId: 232683639