objc: fix envoy_observer native_init

[rebello95]

This was being instantiated in the wrong order, and warning at compile time that the wrong closure types were being assigned to envoy_observer:

library/objective-c/EnvoyEngine.m:228:33: warning: incompatible pointer types initializing 'envoy_on_error_f' (aka 'void (*)(envoy_error, void *)') with an expression of type 'void (void *)' [-Wincompatible-pointer-types]
                                ios_on_complete, ios_on_error, context};
                                ^~~~~~~~~~~~~~~
library/objective-c/EnvoyEngine.m:228:50: warning: incompatible pointer types initializing 'envoy_on_complete_f' (aka 'void (*)(void *)') with an expression of type 'void (envoy_error, void *)' [-Wincompatible-pointer-types]
                                ios_on_complete, ios_on_error, context};
                                                 ^~~~~~~~~~~~

Signed-off-by: Michael Rebello [email protected]

[keith]

You should turn on warnings as errors on CI. You can with --copt=-Werror. After that you might want to tune and enable more warnings as well. If this is too much because of envoy you could also enable it just for this project's cc_library targets.

[rebello95]

@keith that's a great callout. Tried running locally with warnings as errors, but as you mentioned it fails with core Envoy. What would be the best way to run this only on specific Envoy Mobile cc_library targets?

[goaway]

Looks good, thanks for catching this!

Per discussion here and elsewhere, I think @keith's suggestion of running with -Werror is a good one, and I like @junr03's idea of creating a project-specific bazel wrapper rule that adds it (at least for now).

[rebello95]

Filed #339