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The C++ standard for the F-35 Fighter Jet [video]

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327 points AareyBaba | 1 comments | 07 Dec 25 18:07 UTC | HN request time: 0s | source
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time4tea ◴[07 Dec 25 19:31 UTC] No.46184345[source]▶
a = a; // misra

Actual code i have seen with my own eyes. (Not in F-35 code)

Its a way to avoid removing an unused parameter from a method. Unused parameters are disallowed, but this is fine?

I am sceptical that these coding standards make for good code!

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unwind ◴[07 Dec 25 19:43 UTC] No.46184460[source]▶
For C, the proper/expected/standard way to reference a variable without accessing it is a cast to void:

    (void) a;
I'm sure there are commonly-implemented compiler extensions, but this is the normal/native way and should always work.
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amluto ◴[07 Dec 25 22:12 UTC] No.46185753[source]▶
Not if you use GCC.

https://godbolt.org/z/zYdc9ej88

clang gets this right.

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comex ◴[07 Dec 25 22:16 UTC] No.46185785[source]▶
It does work in GCC to suppress unused variable warnings. Just not for function calls I guess.
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1. cminmin ◴[08 Dec 25 08:16 UTC] No.46189702{3}[source]▶
__attribute__((maybe_unused)) or [[maybe_unused]] or such things (dependin on ur spec version i guess?) can be used not to disable a whole line of errors.