Should I avoid the use of inline functions?

[modest coral]

This link: https://www.gnu.org/software/gnulib/manual/html_node/extern-inline.html tells me to do so. It also states that the compiler will handle inlining much better that i could. I searched around and it seems inline (maybe in c specifically) makes your code more error prone than actually helping. It also says that along the register keyword, is something already deprecated.

[red moon]

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[modest slate]

as far as I've understood:

• inline is a compiler hint: nothing forces it to actually inline it, and non inlined methods can be inlined
• inline in a header file allows all users of the headers to see the implementation, but there must still exist a declaration somewhere

imo, once you have -O2 -flto enabled, it's likely inline is not really useful at all

[modest coral]

Sorry I don't know much (don't know anything) about compiler flags other than -I and -Wall

[modest slate]

a register variable has the "behavior" that one cannot take a reference to it, otherwise it's UB

but for the same reason, it likely poorly maps to the fact it will actually be put in register

[modest slate]

-O2 enables code optimization (-O3 is optimizing more for speed, -Os for space)
-flto enables link-time optimization

typically, if your linker can see all the method definitions and is optimizing, it might decide which method deserves to be inlined, even cross source files

I think inline/register are essentially coming from a time where compilers needed help and couldn't really decide on what should be done to activate some speed (like loop unrolling techniques, ...)

maybe with modern compilers and their optimizers, uses of those buddies are less and less relevant

If I got right, even restrict is not that useful anymore

[royal smelt]

I avoid inlining functions for the reasons you and Judekeyser brought up. It simply isn't worth the brainpower, unless you can prove that it results in better Assembly being generated in very optimized circumstances. But most of the time it is just a useless keyword.