iox-#1280 use proper prototypes in C binding

[eboasson]

Declaring a function in C that takes no argument requires "(void)".
With strict warning settings, C compilers will issue a warning.

Fixes #1280

Signed-off-by: Erik Boasson eb@ilities.com

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References

• Closes binding_c needs "proper" prototypes #1280

[elfenpiff]

@eboasson Out of curiosity, do you may have a clue why the apple clang version reports in this case an error and the linux version doesn't.
I recompiled it to see if we may overlooked something in our CI but with:

# clang --version
clang version 13.0.1
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/lib/llvm/13/bin

in combination with -Wall -Werror -pedantic -Wextra -Wconversion -Wuninitialized I do not get any warning.

[MatthiasKillat]

Yes, it is probably required to provide void in C (but not in C++, where it is equivalent to no type in the argument list). See also https://stackoverflow.com/questions/693788/is-it-better-to-use-c-void-arguments-void-foovoid-or-not-void-foo. I have not tried to find at a source in the C standard yet, but I remember having such an issue a long time ago.

[eboasson]

@elfenpiff I suspect it is -Wstrict-prototypes that causes the warning. That gets enabled by Cyclone's CMakeLists.txt for Clang, so you would expect it to fail on Cyclone DDS CI as well, but it doesn't ... 🤔

[codecov]

Codecov Report

Merging #1281 (bb70623) into release_2.0 (46c7cf3) will increase coverage by 0.06%.
The diff coverage is n/a.

@@               Coverage Diff               @@
##           release_2.0    #1281      +/-   ##
===============================================
+ Coverage        78.91%   78.98%   +0.06%     
===============================================
  Files              370      370              
  Lines            14706    14706              
  Branches          2059     2059              
===============================================
+ Hits             11605    11615      +10     
+ Misses            2419     2410       -9     
+ Partials           682      681       -1     

Flag	Coverage Δ
unittests	78.21% <ø> (+0.06%)	⬆️
unittests_timing	15.48% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
iceoryx_posh/source/roudi/port_manager.cpp	85.39% <0.00%> (+1.12%)	⬆️
iceoryx_hoofs/source/concurrent/loffli.cpp	91.42% <0.00%> (+11.42%)	⬆️