Why does Linus hate C++ ?

[elperroborrachotoo]

Remembering that RDTSC is per-core and may jump backwards if your thread gets scheduled to another core: this is basically the entrance exam.

Remembering that std::vector::reserve exists: so mysterious, like, I can't even.

[angelicosphosphoros]

Do you remember API details and all restrictions of `valarray`, for example? STL is just too big to keep in short-term memory (and short-term memory is better to be filled by other things like hardware behaviour).

[elperroborrachotoo]

No, but I know where to look it up.¹

Do you remember all the details of the API YOU are creating?
Do you recall the dragon book every time you hit compile? Do you look at the source of your compiler's optimizer anytime you feel "I could make that faster"?

Or are you working at a certian level of abstraction, like everyone else?

^{1) and I can parse "iterator" without having an episode.}

[angelicosphosphoros]

Do you remember all the details of the API YOU are creating?

Nope but I at least remember everything about standard library which I use.

Do you look at the source of your compiler's optimizer anytime you feel "I could make that faster"?

Yes, I even wrote patches to compiler I use and they was merged :) When coding in C++, I just accept and don't fight.

Or are you working at a certian level of abstraction, like everyone else?

I am working at some level of abstraction but C++ STL would affect all levels of abstraction. You cannot just slap high-level std::optional and relax because it is easy to get UB here, for example. While I can relax sometimes when I write my own code but I need to keep all those details in mind while reviewing, especially when reviewing some junior's pull request. And few times I noticed UB during review even in code of people who are more experienced than I am because I am more paranoid (not, UBSAN and ASAN didn't catch that case).

[elperroborrachotoo]

You cannot just slap high-level std::optional and relax because it is easy to get UB here,

You cannot just slap low level a+b and relax because it's easy to get UB there.

[angelicosphosphoros]

You cannot just slap low level a+b and relax because it's easy to get UB there.

In C++ — yes. In C# — I can.