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0 pointsdavemp3mo ago0 comments

> IMHO the zig footgun story with respect to UB behavior is largely unchanged relative to C/C++

The only major UB from C that zig doesn’t address is use after free afaik. How is that largely unchanged???

Just having an actual strong type system w/o the “billion dollar mistake” is a large change.

0 comments

Depends how you compile it. If you’re compiling ReleaseFast/ReleaseSmall, it’s not very different from C (modulo as you said it has some language features to make it less likely you do it):

* Double free

* Out of bounds array access

* Dereferencing null pointers

* Misaligned pointer dereference

* Accessing uninitialized memory

* Signed integer overflow

* Accessing a union field for which the active tag is something else.

dnautics3mo ago

wow, what a list! all of these are statically analyzable using a slightly hacked zig compiler and a library!

https://github.com/ityonemo/clr

(Btw: you can't null pointer dereference in zig without using the navigation operator which will panic on null; you can't misalign a pointer unless you use @alignCast which will also create a panic)

vlovich1233mo ago

Neat. Why isn’t this in the main compiler / will it be? I’m happy to retract my statement if this becomes actually how zig compiles but it’s not a serious thing as it’s more a PoC of what’s possible today and may break later

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pjmlp3mo ago

I can also analyse C and C++ code for such issues, while keeping using a mature languages ecosystem.

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davempOP3mo ago

This is pretty close to saying Rust is not very different than C because it has the unsafe keyword. That is, either an ignorant (of Zig) or disingenuous statement.

vlovich1233mo ago

To me the zig position is akin to saying that because Asan, TSAn and ubsan exist, c++ is safe because you’re just running optimized for performance.

If you believe I mischaracterized zig, please enlighten me what I got wrong specifically rather than attacking my ad hominem

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vlovich1233mo ago

Depends how you compile it. If you’re compiling ReleaseFast/ReleaseSmall, it’s not very different from C (modulo as you said it has some language features to make it less likely you do it):

* Double free

* Out of bounds array access

* Dereferencing null pointers

* Misaligned pointer dereference

* Accessing uninitialized memory

* Signed integer overflow

* Accessing a union field for which the active tag is something else.

dnautics3mo ago

wow, what a list! all of these are statically analyzable using a slightly hacked zig compiler and a library!

https://github.com/ityonemo/clr

(Btw: you can't null pointer dereference in zig without using the navigation operator which will panic on null; you can't misalign a pointer unless you use @alignCast which will also create a panic)

vlovich1233mo ago

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pjmlp3mo ago

I can also analyse C and C++ code for such issues, while keeping using a mature languages ecosystem.

1 more reply

davempOP3mo ago

This is pretty close to saying Rust is not very different than C because it has the unsafe keyword. That is, either an ignorant (of Zig) or disingenuous statement.

vlovich1233mo ago

To me the zig position is akin to saying that because Asan, TSAn and ubsan exist, c++ is safe because you’re just running optimized for performance.

If you believe I mischaracterized zig, please enlighten me what I got wrong specifically rather than attacking my ad hominem

2 more replies

j / k navigate · click thread line to collapse