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> Oh boy. I see bugs everywhere in C and why the borrow checker exists. Any examples that you could provide? I have been dealing with C/C++ for close to 30 yea

> Oh boy. I see bugs everywhere in C and why the borrow checker exists. Any examples that you could provide? I have been dealing with C/C++ for close to 30 years. Number of times I have shot myself with undefined/unspecified behavior is less than 5.

dafelst 2y ago
The borrow checker isn't just about UB, it is mostly about memory safety. I'm sure you've seen plenty of use-after-frees/use-after-move/dangling pointer type things or null pointer derefs, or data races, etc etc. These are largely impossible to do in safe rust.
jjnoakes 2y ago
The number of times you shot yourself in the foot that you know about. Some of those bullets just haven't landed yet. C and C++ give you very interesting foot-guns: sometimes they go off even when you don't touch them (compiler upgrade, dependencies changing, building on a new architecture, ...)
tsimionescu 2y ago
In 30+ years of experience in C, you haven't used a free()d variable or written past the end of a buffer more than 5 times? If that's true, then you have more care and attention than 99.99% of all C experts.
- kanbankaren 2y ago
  I should have been clear. Of course, I have done such mistakes, but they were caught early in the dev. process. I am talking about bugs that were caught in production due to misunderstanding of C compilers on 16/32 bit processors. I also avoid idioms like *p instead write p[i] whereever possible.
oneshtein 2y ago
Borrow checker checks memory safety. Undefined/unspecified behavior still present in Rust[1]. [1]: https://doc.rust-lang.org/reference/behavior-considered-undefined.html https://doc.rust-lang.org/reference/behavior-considered-unde...
- bombela 2y ago
  Only from code annotated unsafe. In other words, if you do not use the keyword unsafe, you have no undefined behaviors.
eddd-ddde 2y ago
Clearly you must be superhuman then, something as simple as forgetting a null pointer check is bound to hit you every now and then.
- kanbankaren 2y ago
  Of course, I do, but they are caught early in the dev. process. Not in production though.
  - kstrauser 2y ago
    I would contend that’s an unusually sophisticated dev process not used by most.

dafelst 2y ago

The borrow checker isn't just about UB, it is mostly about memory safety. I'm sure you've seen plenty of use-after-frees/use-after-move/dangling pointer type things or null pointer derefs, or data races, etc etc. These are largely impossible to do in safe rust.

jjnoakes 2y ago

The number of times you shot yourself in the foot that you know about. Some of those bullets just haven't landed yet. C and C++ give you very interesting foot-guns: sometimes they go off even when you don't touch them (compiler upgrade, dependencies changing, building on a new architecture, ...)

tsimionescu 2y ago

In 30+ years of experience in C, you haven't used a free()d variable or written past the end of a buffer more than 5 times? If that's true, then you have more care and attention than 99.99% of all C experts.

kanbankaren 2y ago
I should have been clear. Of course, I have done such mistakes, but they were caught early in the dev. process. I am talking about bugs that were caught in production due to misunderstanding of C compilers on 16/32 bit processors. I also avoid idioms like *p instead write p[i] whereever possible.

oneshtein 2y ago

Borrow checker checks memory safety. Undefined/unspecified behavior still present in Rust[1]. [1]: https://doc.rust-lang.org/reference/behavior-considered-undefined.html https://doc.rust-lang.org/reference/behavior-considered-unde...

bombela 2y ago
Only from code annotated unsafe. In other words, if you do not use the keyword unsafe, you have no undefined behaviors.

eddd-ddde 2y ago

Clearly you must be superhuman then, something as simple as forgetting a null pointer check is bound to hit you every now and then.

kanbankaren 2y ago
Of course, I do, but they are caught early in the dev. process. Not in production though.
- kstrauser 2y ago
  I would contend that’s an unusually sophisticated dev process not used by most.