missing cfg flags with cmake build

[simonchatts]

Thanks for all your work on esp-rs!

esp-idf-svc has a bunch of cfg flags, eg esp_idf_comp_esp_netif_enabled, that normally get set by some automatic process I don't understand.

This doesn't work with cmake projects from this template. If you:

• create a std project called "test" with cargo generate --vcs none --git https://github.com/esp-rs/esp-idf-template cmake
• add esp-idf-svc = "0.42.5" to components/rust-test/Cargo.toml
• add use esp_idf_svc::netif; to components/rust-test/src/lib.rs

then you get this error:

error[E0432]: unresolved import `esp_idf_svc::netif`
 --> src/lib.rs:2:5
  |
2 | use esp_idf_svc::netif;
  |     ^^^^^^^^^^^^^^^^^^ no `netif` in the root

If you brute-force it, by adding set(ESP_RUSTFLAGS "--cfg esp_idf_comp_esp_netif_enabled") to components/rust-test/CMakeLists.txt, then this shifts the error onto other missing flags (such as esp_idf_comp_esp_event_enabled).

Any ideas?

[ivmarkov]

esp_idf_comp_* flags get auto-defined by the build system when you enable the corresponding ESP IDF component as part of the CMake build.

[simonchatts]

Aha! Thank you!