Set strict libCompatMode in library.json

[Lenart12]

Platform

ESP32

IDE / Tooling

PlatformIO

What happened?

See here platformio/platformio-core#5171

Stack Trace

In file included from .pio/libdeps/esp32dev/RPAsyncTCP/src/SyncClient.h:14,
                 from .pio/libdeps/esp32dev/RPAsyncTCP/src/SyncClient.cpp:6:
.pio/libdeps/esp32dev/RPAsyncTCP/src/async_config.h:9:25: error: 'MBED_CONF_LWIP_TCP_MSS' was not declared in this scope
   #define TCP_MSS       MBED_CONF_LWIP_TCP_MSS        //(1460)
                         ^~~~~~~~~~~~~~~~~~~~~~
.pio/libdeps/esp32dev/RPAsyncTCP/src/SyncClient.h:40:34: note: in expansion of macro 'TCP_MSS'
     SyncClient(size_t txBufLen = TCP_MSS);
                                  ^~~~~~~
.pio/libdeps/esp32dev/RPAsyncTCP/src/async_config.h:9:25: note: suggested alternative: 'CONFIG_LWIP_TCP_MSS'
   #define TCP_MSS       MBED_CONF_LWIP_TCP_MSS        //(1460)
                         ^~~~~~~~~~~~~~~~~~~~~~
.pio/libdeps/esp32dev/RPAsyncTCP/src/SyncClient.h:40:34: note: in expansion of macro 'TCP_MSS'
     SyncClient(size_t txBufLen = TCP_MSS);
                                  ^~~~~~~
.pio/libdeps/esp32dev/RPAsyncTCP/src/async_config.h:9:25: error: 'MBED_CONF_LWIP_TCP_MSS' was not declared in this scope
   #define TCP_MSS       MBED_CONF_LWIP_TCP_MSS        //(1460)
                         ^~~~~~~~~~~~~~~~~~~~~~
.pio/libdeps/esp32dev/RPAsyncTCP/src/SyncClient.h:41:55: note: in expansion of macro 'TCP_MSS'
     SyncClient(AsyncClient *client, size_t txBufLen = TCP_MSS);

Minimal Reproductible Example (MRE)

Include this library inside another library with strict mode

I confirm that:

• I have read the documentation.
• I have searched for similar discussions.
• I have searched for similar issues.
• I have looked at the examples.
• I have upgraded to the lasted version of ESPAsyncWebServer (and AsyncTCP for ESP32).

[mathieucarbou]

Hello,
This is not the right way since it has some drawbacks also.
Please set your pio file accordingly as in the examples.

[Lenart12]

Can you explain the drawbacks?

[mathieucarbou]

Can you explain the drawbacks?

It's in the forum or commit history or pr - do not remember, but it can have bad impacts elsewhere.

[mathieucarbou]

@Lenart12 : did you find it ?

9423a17

[Lenart12]

No I did search quite a bit of related keywords in commits issues and discussions but nothing came up

[mathieucarbou]

No I did search quite a bit of related keywords in commits issues and discussions but nothing came up

ok. you can look at the link above. the commit hash is found when doing a git log -S libCompatMode

[mitra42]

I can confirm that setting lib_compat_mode = strict in the application works - but its causing another problem. .....

I'm creating a library that depends on ESPAsyncWebServer , this means that every app that depends on my library has to use lib_compat_mode = strict as well. Otherwise the dependency on my library (frugal-iot), installs ESPAsyncWebServer which installs RPAsyncTCP which fails to compile.

I don't mind what I have to do in my frugal-iot to make this work, but would rather not create a point-of-failure for users of my library.

If I read the comment on the commit correctly it suggests that setting "build": { "libCompatMode": "strict" } in my library's library.json would break some other use cases - and I particularly want the library usable in Arduino.IDE as I know some developers who are using my library in that context.

Looking at ESPAsyncWebServer's own library.json it clearly specifies that the dependencies are platform specific, so I'm not sure why PlatformIo is installing a raspberrypi specific dependency when used in an env that specified platform: espressif8266.

Any suggestions for how to make my library as usable as possible appreciated.

[mathieucarbou]

I do not know either why PIO downloads all dependencies, regardless of the platform, but the important point is that they are only considered by the compiler according to the platform.

[mathieucarbou]

also, it is a widely known recommendation to use:

lib_compat_mode = strict
lib_ldf_mode = chain

pioarduino also recommends it.

[mitra42]

OK - I will add that recommendation - I should say it is not accurate to say "that they are only considered by the compiler according to the platform.", this is ONLY true with lib_compat_mode = strict, without that line platformio downloads the library into .pio/libdeps and the compiler then fails to compile it.

[mathieucarbou]

Yes of course that’s what I wanted to say