"C and C++ Prioritize Performance over Correctness" by Russ Cox
https://research.swtch.com/ub

"The original ANSI C standard, C89, introduced the concept of “undefined
behavior,” which was used both to describe the effect of outright bugs
like accessing memory in a freed object and also to capture the fact
that existing implementations differed about handling certain aspects of
the language, including use of uninitialized values, signed integer
overflow, and null pointer handling."

"The C89 spec defined undefined behavior (in section 1.6) as:
Undefined behavior—behavior, upon use of a nonportable or erroneous
program construct, of erroneous data, or of indeterminately-valued
objects, for which the Standard imposes no requirements. Permissible
undefined behavior ranges from ignoring the situation completely with
unpredictable results, to behaving during translation or program
execution in a documented manner characteristic of the environment (with
or without the issuance of a diagnostic message), to terminating a
translation or execution (with the issuance of a diagnostic message)."

"Lumping both non-portable and buggy code into the same category was a
mistake. As time has gone on, the way compilers treat undefined behavior
has led to more and more unexpectedly broken programs, to the point
where it is becoming difficult to tell whether any program will compile
to the meaning in the original source. This post looks at a few examples
and then tries to make some general observations. In particular, today’s
C and C++ prioritize performance to the clear detriment of correctness."

In other news, water is wet.

Lynn

wtorek, 22 sierpnia 2023 o 00:35:05 UTC+2 Lynn McGuire napisał(a):
> "C and C++ Prioritize Performance over Correctness" by Russ Cox

generally such sentences as ""C and C++ Prioritize Performance over Correctness"
are ponys thinking and ponys are wrong...ponys belive in abstract belifs /rules that are wrong

here the idea of c being somewhat genaral language is one of the ideas that are wiser than me imo (and those are special ideas for me becouse ideas that cros over (out) my thinking are special feeling... i wonder if c would look like if i got much more ideas that croses out my mind)

generally i personally i got no troubles with UB i just ignore them, imo the UB probably should just rise warnings esp if some wopuld use soem flag "warning on all undefined behaviours"

thinking that c will allow writing fully portable code on platforms some dont know is imo rather unrealistic (unles maybe c would need to define a wider space of things allowing writing much moire things in defined way - otherwise c code
simply uses non-portabel apis so its not portable) - but c could help
and the idea it helps its rather nice idea i guess

(overally i must say im sad as i feel my skills for logical comprehension of things - some that i got usually high, feels like it dropped down...this may be kinda problem of getting being more idiot (less logic comprehension) when getting old)

wtorek, 22 sierpnia 2023 o 13:33:46 UTC+2 fir napisał(a):
> wtorek, 22 sierpnia 2023 o 00:35:05 UTC+2 Lynn McGuire napisał(a):
> > "C and C++ Prioritize Performance over Correctness" by Russ Cox
> generally such sentences as ""C and C++ Prioritize Performance over Correctness"
> are ponys thinking and ponys are wrong...ponys belive in abstract belifs /rules that are wrong
>
i think even initially c was language that was "outa" ponys world and that makes it maybe so special thing in world

as i said i see in c personally ideas that are outa my mind this way i may say c looks like

1) pony languages and ideas (most of languages)
2) C as i see and understand it
3) C parts that are outa my mind

wtorek, 22 sierpnia 2023 o 13:36:54 UTC+2 fir napisał(a):
> wtorek, 22 sierpnia 2023 o 13:33:46 UTC+2 fir napisał(a):
> > wtorek, 22 sierpnia 2023 o 00:35:05 UTC+2 Lynn McGuire napisał(a):
> > > "C and C++ Prioritize Performance over Correctness" by Russ Cox
> > generally such sentences as ""C and C++ Prioritize Performance over Correctness"
> > are ponys thinking and ponys are wrong...ponys belive in abstract belifs /rules that are wrong
> >
> i think even initially c was language that was "outa" ponys world and that makes it maybe so special thing in world
>
> as i said i see in c personally ideas that are outa my mind this way i may say c looks like
>
> 1) pony languages and ideas (most of languages)
> 2) C as i see and understand it
> 3) C parts that are outa my mind

possibly this "outa c" parts are more far to assembly than my own thinking as i probably think my thinking is probably more close to pascal and assembly
- and this "outa c" (which i sometimes mention) is a big amazing world of ideas im not to comprehand

nothing