Compile issue with clang 13

[akuster]

Openembedded is now using gcc 11 and I am seeing the following build error.

parsec-service/0.7.0-r0/cargo_home/bitbake/psa-crypto-sys-0.8.0/vendor/library/psa_crypto.c:4590:12: error: parameter 'output_size' set but not used [-Werror,-Wunused-but-set-parameter]
| size_t output_size,
| ^
| 1 error generated.

Looking @ Mbedlts, it appears the offending function has been removed via commit:

commit 6d05173359fb53eb2a893e6834a221a4262233da
Author: Ronald Cron ronald.cron@arm.com
Date: Thu Oct 1 14:10:20 2020 +0200

psa: Add mbedtls_psa_cipher_xyz() APIs

Signed-off-by: Ronald Cron <ronald.cron@arm.com>

I think there is a mismatch somewhere.

[hug-dev]

Hey 👋!!
Thanks for the bug report.

Looks like this commit is part of this PR which was not included in the latest 2.26.0 release 😢
We are currently using 2.25.0 in this repo and ideally we would only point to Mbed TLS release versions. We could cherry-pick a bug fix on top of our git submodule but 6d05173359fb53eb2a893e6834a221a4262233da seems to be way bigger than just this bug fix so Im wondering if other things will break if we try just to apply that.

This looks like a Mbed TLS bug, is there anything reported on their side?

I am also wondering if you could remove the -Wunused-but-set-parameter flag by setting your own CFLAGS before compiling psa-crypto with GCC 11

[hug-dev]

Mbed TLS 3.0.0 was just released. If the fix is included there, we can just use that in this crate and it should work ™️

[ionut-arm]

It is, indeed, included! However we need to see just how different Mbed TLS 3.0.0 is, at least in terms of PSA Crypto implementation

[akuster]

Apologies for the slow response. I have tried -Wunused-but-set-parameter but it does not propagate down to psa-crypto in the context of how this package is included within the OE build env. Sorry I can not be much help.

[hug-dev]

The three linked PR above confirms that there were breaking changes in between the Mbed TLS version we use (2.25.0) and 3.0.0. If we update psa-crypto to match 3.0.0, it would mean that we won't be able to dynamically link with an older version than that.

If think that's fine, but this will need notice where it causes a stability problem (for example in Parsec where we have to bump our minimum Mbed TLS version to 3.0.0).

[anta5010]

@akuster The parsec-service recipe uses clang toolchain and the error you see is caused by meta-clang move to not yet released clang-13. I will update the recipe to use gcc toolchain instead for the current version of parsec service. The future version of parsec most likely will use a new version of mbedtls.

[hug-dev]

I guess that is closed now but feel free to re-open if the problem persists!