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stkdump

I mean practically speaking in C++ we have (it just hasn't made it to the standard):

1. char 8 bit

2. short 16 bit

3. int 32 bit

4. long long 64 bit

5. arithmetic is 2s complement

6. IEEE floating point (float is 32, double is 64 bit)

Along with other stuff like little endian, etc.

Some people just mistakenly think they can't rely on such stuff, because it isn't in the standard. But they forget that having an ISO standard comes on top of what most other languages have, which rely solely on the documentation.

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I work every day with real-life systems where int can be 32 or 64 bits, long long can be 64 or 128 bits, long double can be 64 or 80 or 128 bits, some systems do not have IEEE 754 floating point (no denormals!) some are big endian and some are little endian. These things are not in the language standard because they are not standard in the real world.

Practically speaking, the language is the way it is, and has succeeded so well for so long, because it meets the requirements of its application.

There are also people who write COBOL for a living. What you say is not relevant at all for 99.99% of C++ code written today. Also, all compilers can be configured to be non-standard compliant in many different ways, the classic example being -fno-exceptions. Nobody says all kinds of using a standardized language must be standard conformant.

> (it just hasn't made it to the standard)

That's the problem

You are aware that D and rust and all the other languages this is being compared to don't even have an ISO standard, right?

Yeah, so their documentation serves as the authority on how you're supposed to write your code for it to be "correct D" or "correct Rust". The compiler implementors write their compilers against the documentation (and vice versa). That documentation is clear on these things.

In C, the ISO standard is the authority on how you're supposed to write your code for it to be "correct C". The compiler implementors write their compilers against the ISO standard. That standard is not clear on these things.

I don't think this is true. The target audience of the ISO standard is the implementers of compilers and other tools around the language. Even the people involved in creating it make that clear by publishing other material like the core guidelines, conference talks, books, online articles, etc., which are targeted to the users of the language.

Core guidelines, conference talks, books, online articles, etc. are not authoritative. If I really want to know if my C code is correct C, I consult the standard. If the standard and an online article disagrees, the article is wrong, definitionally.

Correction: if you want to know if your compiler is correct, you look at the ISO standard. But even as a compiler writer, the ISO standard is not exhaustive. For example the ISO standard doesn't define stuff like include directories, static or dynamic linking, etc.

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