fix build with gcc-15

[heitbaum]

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You are under no obligation whatsoever to provide any bug fixes, patches, or
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• Version of iperf3 (or development branch, such as master or
  3.1-STABLE) to which this pull request applies: master and 3.17.1

• Issues fixed (if any): compile with gcc-15

• Brief description of code changes (suitable for use as a commit message): update declarations to include types as required by gcc-15 and -std=c23

[bmah888]

Thanks for the PR, we'll take a look!

[bmah888]

This looks pretty good, although my ability to test this is limited. Per #1838 (comment) would you know if this is the same fix that was applied to iperf 3.18-2 in the Debian package repository?

[userdocs]

I can test it.

current master will fail with gcc 15 https://github.com/userdocs/iperf3-static-test/actions/runs/14755488675

This patch branch does not - https://github.com/userdocs/iperf3-static-test/actions/runs/14755738953/job/41423407651

[userdocs]

@bmah888

https://sources.debian.org/patches/iperf3/3.18-2/02-gcc15.patch/

[bmah888]

@bmah888

https://sources.debian.org/patches/iperf3/3.18-2/02-gcc15.patch/

Perfect, thanks the help @userdocs!

[bmah888]

Thanks for the PR @heitbaum , or should I call you Mr. Bump? :-)

This looks good and it's now been tested by @userdocs , I will merge shortly.

[userdocs]

Just to confirm it built fine on master with gcc15

https://github.com/userdocs/iperf3-static-test/actions/runs/14802833500

[bmah888]

@userdocs Thanks for the confirmation!

[heitbaum]

Thanks for the PR @heitbaum , or should I call you Mr. Bump? :-)

heitbaum is fine :-) as the LE distro packing lead, the team thought Mr.Bump suited, so the emoji stuck :-)