Re: I was wrong about gcc's inlining behavior

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From	Bo Persson <bo@bo-persson.se>
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Subject	Re: I was wrong about gcc's inlining behavior
Date	Fri, 21 Oct 2022 16:41:44 +0200
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On 2022-10-21 at 13:44, Juha Nieminen wrote:
> (I don't know if this applies to other compilers like clang. Could be.)
> 
> For the longest time I thought that if gcc sees a function implementation
> at the place where the function is being called, then it doesn't matter
> if the keyword 'inline' appears before that function implementation or
> not. I thought that gcc just ignores that keyword when making inlining
> decisions. (After all, why wouldn't it?)
> 
> Just now, however, I got a concrete counter-example to this.
> 

> 
> So it appears that I have been wrong: When it comes to functions visible
> at the global scope, the 'inline' keyword can make a huge difference,
> even when the implementations are seen by the compiler at the call
> places.
> 

It probably doesn't make a huge difference in general, but if your 
function is 'close' to getting inlined, an actual 'inline' keyword might 
add a few points to the heuristics, and tip it over the decision point.

Thread

I was wrong about gcc's inlining behavior Juha Nieminen <nospam@thanks.invalid> - 2022-10-21 11:44 +0000
  Re: I was wrong about gcc's inlining behavior Michael S <already5chosen@yahoo.com> - 2022-10-21 07:01 -0700
    Re: I was wrong about gcc's inlining behavior Juha Nieminen <nospam@thanks.invalid> - 2022-10-24 06:45 +0000
      Re: I was wrong about gcc's inlining behavior Michael S <already5chosen@yahoo.com> - 2022-10-24 10:11 -0700
        Re: I was wrong about gcc's inlining behavior scott@slp53.sl.home (Scott Lurndal) - 2022-10-24 17:54 +0000
  Re: I was wrong about gcc's inlining behavior Bo Persson <bo@bo-persson.se> - 2022-10-21 16:41 +0200
  Re: I was wrong about gcc's inlining behavior Andrey Tarasevich <andreytarasevich@hotmail.com> - 2022-10-21 08:47 -0700
    Re: I was wrong about gcc's inlining behavior scott@slp53.sl.home (Scott Lurndal) - 2022-10-21 16:04 +0000
  Re: I was wrong about gcc's inlining behavior Marcel Mueller <news.5.maazl@spamgourmet.org> - 2022-10-22 09:21 +0200
    Re: I was wrong about gcc's inlining behavior scott@slp53.sl.home (Scott Lurndal) - 2022-10-22 15:05 +0000
    Re: I was wrong about gcc's inlining behavior Juha Nieminen <nospam@thanks.invalid> - 2022-10-24 07:00 +0000

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