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> This seems totally misconceived to me as a basis for standardizing a language in 2022. You are optimizing for the few at the expense of the many. Sure, but i

> This seems totally misconceived to me as a basis for standardizing a language in 2022. You are optimizing for the few at the expense of the many. Sure, but it's the same line of reasoning that made C relevant in the first place, and keeps it relevant today - some library your dad wrote for a PDP-whatever is still usable today on your laptop running Windows 10. Because it's antiquated, it's also extremely easy to support, and to port to new and/or exotic platforms.

ErikCorry 4y ago
The library my dad wrote (lol) for the PDP-11 is probably full of undefined behaviour and won't work now that optimizers are using any gap in the standard to miscompile code.
- flqn 4y ago
  What a useless and jaded assumption that code written in the past is bad.
  - jolux 4y ago
    The assumption being made here is "any useful C program relies on undefined behavior" which is pretty much true.
    - ErikCorry 4y ago
      Yes and I'm sure it's doubly true of code that was written before the C standards were written.
    - pantalaimon 4y ago
      That sounds like a strong take - to you have examples? Compiling with -Wall -Werror is pretty much standard those days.
      - morelisp 4y ago
        -Wall -Werror is mostly designed to catch dangerous but totally well-defined idioms, not UB. It doesn't warn on every signed arithmetic operation or unchecked array access, for example.
      - jolux 4y ago
        See "useful" — it may not be not quite as strong as you're thinking. It may be possible to write a minimal C program without UB, but I'm thinking of larger programs, more than a few hundred lines. Common UB includes: array access out of bounds, dereferencing a null pointer, use after free, use of uninitialized variables. -Wall -Werror can catch some instances of some types of UB, and runtime libraries like UBSan can catch more. But they're not exhaustive.
  - ErikCorry 4y ago
    I certainly didn't say it was bad. Just that it went outside the boundaries of a standard that was written 25 years later.
- jolux 4y ago
  > using any gap in the standard to miscompile code For code to be miscompiled, there has to be a definition of what correctly compiling it would mean, and if there were, it would not be undefined behavior.
  - ErikCorry 4y ago
    Instead of "miscompiled" you can read "Doesn't do what it did on the PDP-11 with the compilers of the time".
  - xg15 4y ago
    Yeah, but if that definition is constantly shifting, you cannot expect it to work with existing codebases.
    - jolux 4y ago
      Well yeah — therein lies the problem with a language with pervasive undefined behavior.
  - temac 4y ago
    The standard doesn't do that often, but it does sometimes. E.g. realloc to null which was previously defined, and is now UB :(
    - ErikCorry 4y ago
      We are taking about code written before the standard so every bit of UB in the standard is in play here. Eg the fact that overflowing a signed int can cause the compiler to go amuck would certainly be a surprise to the person who wrote code for the PDP-11.
raverbashing 4y ago
> PDP-whatever is still usable today on your laptop running Windows 10 No, it isn't. Go on. Go ahead and try See it break in a million weird ways. (Or, for a start, it will have the K&R C format, which is a pain to maintain) "If your computer doesn't have 8-bit bytes" at this day and age? It belongs in a dumpster, sorry. (I think the only "modern" arch that does this is PIC, and even only for program data - where you're not running anything "officially" C89 or later)
- icedchai 4y ago
  When I first learned C, it was K&R, pre-ANSI with old style function parameters. It is trivial to convert to ANSI C. The truth is C has barely changed in decades.
- ryukoposting 4y ago
  You should take a look at plan9port - a bunch of userspace tools from Plan 9, carefully ported to Linux with few changes. Maybe that's not PDP-whatever, but it is Sun-whatever. Either way, it's code that was written decades ago for a dead architecture.

ErikCorry 4y ago

The library my dad wrote (lol) for the PDP-11 is probably full of undefined behaviour and won't work now that optimizers are using any gap in the standard to miscompile code.

flqn 4y ago
What a useless and jaded assumption that code written in the past is bad.
- jolux 4y ago
  The assumption being made here is "any useful C program relies on undefined behavior" which is pretty much true.
  - ErikCorry 4y ago
    Yes and I'm sure it's doubly true of code that was written before the C standards were written.
  - pantalaimon 4y ago
    That sounds like a strong take - to you have examples? Compiling with -Wall -Werror is pretty much standard those days.
    - morelisp 4y ago
      -Wall -Werror is mostly designed to catch dangerous but totally well-defined idioms, not UB. It doesn't warn on every signed arithmetic operation or unchecked array access, for example.
    - jolux 4y ago
      See "useful" — it may not be not quite as strong as you're thinking. It may be possible to write a minimal C program without UB, but I'm thinking of larger programs, more than a few hundred lines. Common UB includes: array access out of bounds, dereferencing a null pointer, use after free, use of uninitialized variables. -Wall -Werror can catch some instances of some types of UB, and runtime libraries like UBSan can catch more. But they're not exhaustive.
- ErikCorry 4y ago
  I certainly didn't say it was bad. Just that it went outside the boundaries of a standard that was written 25 years later.
jolux 4y ago
> using any gap in the standard to miscompile code For code to be miscompiled, there has to be a definition of what correctly compiling it would mean, and if there were, it would not be undefined behavior.
- ErikCorry 4y ago
  Instead of "miscompiled" you can read "Doesn't do what it did on the PDP-11 with the compilers of the time".
- xg15 4y ago
  Yeah, but if that definition is constantly shifting, you cannot expect it to work with existing codebases.
  - jolux 4y ago
    Well yeah — therein lies the problem with a language with pervasive undefined behavior.
- temac 4y ago
  The standard doesn't do that often, but it does sometimes. E.g. realloc to null which was previously defined, and is now UB :(
  - ErikCorry 4y ago
    We are taking about code written before the standard so every bit of UB in the standard is in play here. Eg the fact that overflowing a signed int can cause the compiler to go amuck would certainly be a surprise to the person who wrote code for the PDP-11.

raverbashing 4y ago

> PDP-whatever is still usable today on your laptop running Windows 10 No, it isn't. Go on. Go ahead and try See it break in a million weird ways. (Or, for a start, it will have the K&R C format, which is a pain to maintain) "If your computer doesn't have 8-bit bytes" at this day and age? It belongs in a dumpster, sorry. (I think the only "modern" arch that does this is PIC, and even only for program data - where you're not running anything "officially" C89 or later)

icedchai 4y ago
When I first learned C, it was K&R, pre-ANSI with old style function parameters. It is trivial to convert to ANSI C. The truth is C has barely changed in decades.
ryukoposting 4y ago
You should take a look at plan9port - a bunch of userspace tools from Plan 9, carefully ported to Linux with few changes. Maybe that's not PDP-whatever, but it is Sun-whatever. Either way, it's code that was written decades ago for a dead architecture.