Re: Baby X is bor nagain

On 24/06/2024 18:02, Scott Lurndal wrote:

bart <bc@freeuk.com> writes:

On 24/06/2024 16:10, Michael S wrote:

 

But my project has much more than 34 modules. 164 modules compiled
during build + several dozens in libraries.

>
Does that matter? My example is a smaller project, but I'm comparing the
rate of compilation not total time.
>
If you want a bigger example, yesterday I posted one involving 140 .c
files, total EXE size is 5MB (don't know .text as this is ELF format).

 Why do you believe that the size of the executable is interesting?

Well, what metric IS interesting?
You seem to not care whether an executable is 10KB, 10MB, or 10GB. You really don't think there's correspondence with build-time?

 Why do you think you think 5MB is unusual

MS claimed that my project was smaller than his. So I found a bigger one.
 > if you don't know anything
 > about ELF?
What's that going to do with the price of fish? ELF is another executable format, but my tools can't look inside it.

 The 'size' command will tell you the text size, although the text size
is a meaningless parameter in modern virtual memory systems which
load pages on demand.

The .text was also something introduced by MS.

$ file /tmp/a
/tmp/a: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.32, BuildID[sha1]=12944219f87c74b03ec19d1d693771e12416dd81, not stripped
$ size /tmp/a
    text    data     bss     dec     hex filename
    1257     548       4    1809     711 /tmp/a
$ ls -l /tmp/a
-rwxrwxr-x. 1 scott scott 8501 Jun 20 07:45 /tmp/a
  When the average disk holds 1 TB, 5MB is not even in the noise.

And what does /that/ have to do with anything?
One metric I find useful with my compiler work is how many MB per second they can produce from direct compilation. And 5MB per second is faster than 50KB per second.
It took gcc 17-38 seconds to build that 5MB product in WSL; that's pretty slow.
If you want to ignore that simple fact then <shrug>. The common themes in this newsgroup is first to defend the design of the C language, and second to defend the behaviour and performance of gcc.
Maybe more people should take an interest.
It would be funny if gcc suddenly doubled in speed overnight because of some stupid oversight that nobody had bothered to investigate.
Because lines/second or MB/second or anything else is 'uninteresting'.
BTW how slow does a tool have to get before YOU start asking questions?

>
-O2 took just over twice as long as -O0.
>
But I guess every single example I come up with is 'exceptional'.

 By definition.
 

Maybe
what's exceptional is that I measuring the runtime of the compiler, and
not all sorts of other junk.

 You seem to be measuring the wall-clock time which is influenced by
factors other than the size of the source file including other processes
running during your compile.
 

Yes, it is during that same time period that people waiting for it to complete have to sit twiddling their thumbs.