CMakeLists: Avoid implicit function declarations on GNU/Linux

[fweimer-rh]

Future compilers are likely to require that all called functions are properly declared.

Include <unistd.h> for the close function. Do not call the undeclared __tls_get_addr function; rely on __thread support for feature probing. Define _GNU_SOURCE to obtain prototypes of fallocate and memmem.

Related to:

• https://fedoraproject.org/wiki/Changes/PortingToModernC
• https://fedoraproject.org/wiki/Toolchain/PortingToModernC

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Testing Before we can approve your change; please submit the following in a comment:

• [N/A] Example configuration file for the change
• [N/A] Debug log output from testing the change

• [N/A] Attached Valgrind output that shows no leaks or memory corruption was found

If this is a change to packaging of containers or native binaries then please confirm it works for all targets.

• [N/A] Attached local packaging test output showing all targets (including any new ones) build.

Documentation

• [N/A] Documentation required for this feature

Backporting

• [ ] Backport to latest stable release.

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Fluent Bit is licensed under Apache 2.0, by submitting this pull request I understand that this code will be released under the terms of that license.

[patrick-stephens]

@fweimer-rh thanks for this, could you just make sure your commits are signed off? See the failed check for details and how to fix: https://github.com/fluent/fluent-bit/pull/6704/checks?check_run_id=10723974841

From https://github.com/fluent/fluent-bit/blob/master/CONTRIBUTING.md:

When running the git commit command, make sure you are using the -s flag, that will add a Signed-off comment in the patch description. If your commit is not signed-off, Github DCO check will fail and your contribution will not be reviewed until that get's fixed.

[github-actions[bot]]

This PR is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 10 days.

[fweimer-rh]

I think this is still relevant.

[patrick-stephens]

We need to confirm this compiles for all targets (per the PR template) so I've triggered that test but really that can be done locally beforehand too.

[github-actions[bot]]

This PR is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 10 days.

[fweimer-rh]

We need to confirm this compiles for all targets (per the PR template) so I've triggered that test but really that can be done locally beforehand too.

The link in the template does not work, the directory .github/packaging does not exist anymore.

It looks like the testing passed, what are the next steps here?

[patrick-stephens]

We need to confirm this compiles for all targets (per the PR template) so I've triggered that test but really that can be done locally beforehand too.

The link in the template does not work, the directory .github/packaging does not exist anymore.

It looks like the testing passed, what are the next steps here?

None, all good from that side.

The actual script is here but looks like it goes funky with PRs: https://github.com/fluent/fluent-bit/blob/master/packaging/local-build-all.sh

[github-actions[bot]]

This PR is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 10 days.

[fweimer-rh]

I've rebased this and added a couple more fixes for type errors (currently needed by GCC 14).

[github-actions[bot]]

This PR is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 10 days.

[github-actions[bot]]

This PR is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 10 days.

[github-actions[bot]]

This PR is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 10 days.