/long_compile_rustc_1.59.0

Primary LanguageRust

About

This repo demonstrates unusually long compile times when building with optimizations due to the optimizer trying to optimize serde_json::from_str::<BigStruct>(include_str!("big_json.json"))

This bug exists in stable rustc 1.59.0

Build with optimizations to see the bug, code to generate the struct and json are included so you can add more or fewer fields easily.

$ cargo build --release

Quick and dirty benchmark of cargo build --release from a clean state on my machine, ryzen 3900x

Size | 1.58.1 | 1.59.0
----------------------
50   |     8s |    10s
100  |    12s |    36s
200  |    31s |   427s
300  |    83s | >1800s