esp-idf: NimBLE: Build fails with only Observer role enabled (IDFGH-8308)

Answers checklist.

• I have read the documentation ESP-IDF Programming Guide and the issue is not addressed there.
• I have updated my IDF branch (master or release) to the latest version and checked that the issue is present there.
• I have searched the issue tracker for a similar issue and not found a similar issue.

IDF version.

v.4.4.2

Operating System used.

macOS

How did you build your project?

VS Code IDE

If you are using Windows, please specify command line type.

No response

What is the expected behavior?

Build should be successful with no errors.

What is the actual behavior?

Build returns errors and doesn’t complete.

Steps to reproduce.

1. Create a sample project or test on an existing project
2. Enable BT and select NimBLE
3. Disable al roles but Observer (menuconfig)
4. Build the project

Build or installation Logs.

...
/Users/raver/espressif/esp-idf-v4.4.2/components/bt/host/nimble/nimble/nimble/host/src/ble_gap.c: In function 'ble_gap_disc_report':
/Users/raver/espressif/esp-idf-v4.4.2/components/bt/host/nimble/nimble/nimble/host/src/ble_gap.c:1007:5: error: implicit declaration of function 'ble_gap_master_extract_state'; did you mean 'ble_gap_slave_extract_cb'? [-Werror=implicit-function-declaration]
     ble_gap_master_extract_state(&state, 0);
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
     ble_gap_slave_extract_cb
/Users/raver/espressif/esp-idf-v4.4.2/components/bt/host/nimble/nimble/nimble/host/src/ble_gap.c:1008:9: error: implicit declaration of function 'ble_gap_has_client'; did you mean 'ble_gap_mtu_event'? [-Werror=implicit-function-declaration]
     if (ble_gap_has_client(&state)) {
         ^~~~~~~~~~~~~~~~~~
         ble_gap_mtu_event
/Users/raver/espressif/esp-idf-v4.4.2/components/bt/host/nimble/nimble/nimble/host/src/ble_gap.c: In function 'ble_gap_reset_state':
/Users/raver/espressif/esp-idf-v4.4.2/components/bt/host/nimble/nimble/nimble/host/src/ble_gap.c:1424:5: error: implicit declaration of function 'ble_gap_master_failed'; did you mean 'ble_gap_adv_finished'? [-Werror=implicit-function-declaration]
     ble_gap_master_failed(reason);
     ^~~~~~~~~~~~~~~~~~~~~
     ble_gap_adv_finished
/Users/raver/espressif/esp-idf-v4.4.2/components/bt/host/nimble/nimble/nimble/host/src/ble_gap.c: In function 'ble_gap_disc_cancel_no_lock':
/Users/raver/espressif/esp-idf-v4.4.2/components/bt/host/nimble/nimble/nimble/host/src/ble_gap.c:4420:5: error: implicit declaration of function 'ble_gap_master_reset_state'; did you mean 'ble_gap_slave_reset_state'? [-Werror=implicit-function-declaration]
     ble_gap_master_reset_state();
     ^~~~~~~~~~~~~~~~~~~~~~~~~~
     ble_gap_slave_reset_state
/Users/raver/espressif/esp-idf-v4.4.2/components/bt/host/nimble/nimble/nimble/host/src/ble_gap.c: In function 'ble_gap_disc':
/Users/raver/espressif/esp-idf-v4.4.2/components/bt/host/nimble/nimble/nimble/host/src/ble_gap.c:4748:9: error: implicit declaration of function 'ble_gap_master_set_timer'; did you mean 'ble_gap_master_timer'? [-Werror=implicit-function-declaration]
         ble_gap_master_set_timer(duration_ticks);
         ^~~~~~~~~~~~~~~~~~~~~~~~
         ble_gap_master_timer
At top level:
/Users/raver/espressif/esp-idf-v4.4.2/components/bt/host/nimble/nimble/nimble/host/src/ble_gap.c:835:1: warning: 'ble_gap_adv_finished' defined but not used [-Wunused-function]
 ble_gap_adv_finished(uint8_t instance, int reason, uint16_t conn_handle,
 ^~~~~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
[1073/1128] Building CXX object esp-idf/asio/CMakeFiles/__idf_asio.dir/asio/asio/src/asio.cpp.obj
ninja: build stopped: subcommand failed.

More Information.

Build fails with other IDF versions such as v4.3.4. No build errors with v4.2.4 or v5.0-beta1.