neon @0.30.2: configure failure due to implicit declaration of functions

[AP1010]

configure stage fails with:

...
checking for library containing socket... not found
configure: error: could not find library containing socket
...

[ryandesign (Ryan Schmidt)]

Could be the ubiquitous implicit declaration of function error. Please attach the config.log.

[AP1010]

Logs added

[AP1010]

Indeed, it does seem to be the "implicit declaration invalid in C99 issue". The port builds with configure.compiler=macports-clang-9.0

[Tatsh (Andrew Udvare)]

Replying to AP1010:

Indeed, it does seem to be the "implicit declaration invalid in C99 issue". The port builds with configure.compiler=macports-clang-9.0

Also works with macports-clang-11.

[jungx098]

The root cause is that clang 12 enables -Werror by default. Not sure if Apple will roll back this feature.

One workaround is to add -Wno-error=all to CFLAGS.

I made a quick patch: ​https://github.com/macports/macports-ports/compare/master...jungx098:neon

[kencu (Ken)]

Replying to jungx098:

The root cause is that clang 12 enables -Werror by default. Not sure if Apple will roll back this feature.

I don't think it's a blanket -Werror, but they do generate an error on implicit function definitions, by default, as of Xcode12.

One workaround is to add -Wno-error=all to CFLAGS.

Turning off the error can be done more specifically for that error as well, or you can build with a non-Apple clang compiler like macports-clang-10, however apparently if you fix the build that way, it remains broken on all the new Apple Silicon machines, that require a proper header and a proper function definition for every function.

So MacPorts is not accepting the fix of turning off the error or building with a non-Apple clang compiler as a fix for this issue, as we'll all just have to come right back to this same issue again in a few months and fix it properly anyway.

As a fix for your own personal system, no problem of course -- it's your system, you can do anything you want with it!

[kencu (Ken)]

See this message for many gory details <​https://lists.macports.org/pipermail/macports-dev/2020-November/042648.html>

[jungx098]

Replying to kencu:

See this message for many gory details <​https://lists.macports.org/pipermail/macports-dev/2020-November/042648.html>

Thanks for the details. It feels like non-trivial.

[mf2k (Frank Schima)]

Has duplicate #62076.

[jboydon (John Boydon)]

I am struggling with neon installation. Can someone tell me the proper way to specify CFLAGS=-Wno-error=all in the command line?

I have tried with the following without success:

sudo port -v install configure.cflags="-Wno-error=all"
sudo port -v install configure.cflags-append="-Wno-error=all"

Thanks

john

[sdguip]

Compiled with success:

sudo port install neon configure.cflags=-Wno-error=all

[ryandesign (Ryan Schmidt)]

After an unsuccessful initial attempt to fix it myself, I've ​reported the problem to the developers.