4 ms·

Does C# not have a GC? I thought that would immediately disqualify it for kernel work.

theta_d 4y ago
It does have GC but that is not the point being made. I believe the point the author is making is that other languages provide better safety than C and have faster compile times than Rust, therefore Rust should be able to improve its compile times.
- rbanffy 4y ago
  GC is not a roadblock for OS kernel work. Smalltalk is itself an OS and had GC from the start. IBM's i (the descendant of OS/400) most likely has GC as part of its kernel. Lisp machines had hardware-assisted GC. What you may want to try to avoid is complex and non-deterministic GC, which makes it harder to reason about.
- pedrocr 4y ago
  If those languages achieve their memory safety at runtime, like C# does with GC, then that becomes relevant to the point of the compile time performance. The C# compiler has to do less as that complexity has been pushed elsewhere with different tradeoffs.
  - pjmlp 4y ago
    Rust safety with runtime dependencies, Vec bounds checking, Arc and Rc datatypes. Ada with SPARK 2014 formal proofs, for your other part of the remark.
5e92cb50239222b 4y ago
For Linux kernel work. https://www.microsoft.com/en-us/research/project/singularity https://www.microsoft.com/en-us/research/project/singularity https://en.wikipedia.org/wiki/SharpOS https://en.wikipedia.org/wiki/SharpOS
pjmlp 4y ago
For Linux yes, for those that aren't blinded by anti-GC religion, no. https://www.wildernesslabs.co/ https://www.wildernesslabs.co/
- Ygg2 4y ago
  Anti GC isn't a religion. GC is a performance cliff in some cases.
  - pjmlp 4y ago
    It is certainly a religion, as most people that advocate against it hardly ever learned to use a profiler, or bothered to learn that not all GC languages are alike, and many of them offer the same capabilities like C and C++ for low level coding.
    - Ygg2 4y ago
      It's not, collaborating on a C# game engine and what I've seen is basically a lot of skirting around GC, because it's impact shows up in profiler. It has gotten to a point arrays and stack alloc are prefered over List and HashSet were basically forbidden in the hottest path. Except most of C# ecosystem relies on classes and GC. A lot of these problems are caused by overuse of GC-ed classes, and their ease of use.
      - pjmlp 4y ago
        Don't confuse Unity runtime with C#, specially since it lacks all the nice features post C# 7. C and C++ aren't immune to heap abuse as well. You do on C# just like on them, think about data structures, and avoid heap during render loop
        Ygg2 4y ago
        Did I mention Unity? It was a independently developed engine. The engine is in C# 10. They still ran into limitations where basically "This would be a lot easier if we didn't have GC".

It does have GC but that is not the point being made. I believe the point the author is making is that other languages provide better safety than C and have faster compile times than Rust, therefore Rust should be able to improve its compile times.

rbanffy 4y ago
GC is not a roadblock for OS kernel work. Smalltalk is itself an OS and had GC from the start. IBM's i (the descendant of OS/400) most likely has GC as part of its kernel. Lisp machines had hardware-assisted GC. What you may want to try to avoid is complex and non-deterministic GC, which makes it harder to reason about.
pedrocr 4y ago
If those languages achieve their memory safety at runtime, like C# does with GC, then that becomes relevant to the point of the compile time performance. The C# compiler has to do less as that complexity has been pushed elsewhere with different tradeoffs.
- pjmlp 4y ago
  Rust safety with runtime dependencies, Vec bounds checking, Arc and Rc datatypes. Ada with SPARK 2014 formal proofs, for your other part of the remark.

5e92cb50239222b 4y ago

For Linux kernel work. https://www.microsoft.com/en-us/research/project/singularity https://www.microsoft.com/en-us/research/project/singularity https://en.wikipedia.org/wiki/SharpOS https://en.wikipedia.org/wiki/SharpOS

pjmlp 4y ago

For Linux yes, for those that aren't blinded by anti-GC religion, no. https://www.wildernesslabs.co/ https://www.wildernesslabs.co/

Ygg2 4y ago
Anti GC isn't a religion. GC is a performance cliff in some cases.
- pjmlp 4y ago
  It is certainly a religion, as most people that advocate against it hardly ever learned to use a profiler, or bothered to learn that not all GC languages are alike, and many of them offer the same capabilities like C and C++ for low level coding.
  - Ygg2 4y ago
    It's not, collaborating on a C# game engine and what I've seen is basically a lot of skirting around GC, because it's impact shows up in profiler. It has gotten to a point arrays and stack alloc are prefered over List and HashSet were basically forbidden in the hottest path. Except most of C# ecosystem relies on classes and GC. A lot of these problems are caused by overuse of GC-ed classes, and their ease of use.
    - pjmlp 4y ago
      Don't confuse Unity runtime with C#, specially since it lacks all the nice features post C# 7. C and C++ aren't immune to heap abuse as well. You do on C# just like on them, think about data structures, and avoid heap during render loop
      - Ygg2 4y ago
        Did I mention Unity? It was a independently developed engine. The engine is in C# 10. They still ran into limitations where basically "This would be a lot easier if we didn't have GC".