I have async code, and I'm using a library that is unfortunately sync. That library uses the blocking interface of reqwest internally.

I'm running into issues when instantiating that struct from within async code. I'm only calling the actual blocking code from a rayon pool, so that should be fine. I don't understand why instantiating it would cause issues though:

thread 'main' panicked at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/runtime/blocking/shutdown.rs:51:21:
Cannot drop a runtime in a context where blocking is not allowed. This happens when a runtime is dropped from within an asynchronous context.
stack backtrace:
   0: __rustc::rust_begin_unwind
             at /rustc/1159e78c4747b02ef996e55082b704c09b970588/library/std/src/panicking.rs:697:5
   1: core::panicking::panic_fmt
             at /rustc/1159e78c4747b02ef996e55082b704c09b970588/library/core/src/panicking.rs:75:14
   2: tokio::runtime::blocking::shutdown::Receiver::wait
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/runtime/blocking/shutdown.rs:51:21
   3: tokio::runtime::blocking::pool::BlockingPool::shutdown
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/runtime/blocking/pool.rs:263:29
   4: <tokio::runtime::blocking::pool::BlockingPool as core::ops::drop::Drop>::drop
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/runtime/blocking/pool.rs:284:14
   5: core::ptr::drop_in_place<tokio::runtime::blocking::pool::BlockingPool>
             at /home/arvid/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:804:1
   6: core::ptr::drop_in_place<tokio::runtime::runtime::Runtime>
             at /home/arvid/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ptr/mod.rs:804:1
   7: reqwest::blocking::wait::enter
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/reqwest-0.12.23/src/blocking/wait.rs:80:21
   8: reqwest::blocking::wait::timeout
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/reqwest-0.12.23/src/blocking/wait.rs:13:5
   9: reqwest::blocking::client::ClientHandle::new
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/reqwest-0.12.23/src/blocking/client.rs:1417:15
  10: reqwest::blocking::client::ClientBuilder::build
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/reqwest-0.12.23/src/blocking/client.rs:116:9
  11: reqwest::blocking::client::Client::new
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/reqwest-0.12.23/src/blocking/client.rs:1219:30
  12: debuginfod::client::Client::new
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/debuginfod-0.2.1/src/client.rs:70:18
  13: debuginfod::client::Client::from_env
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/debuginfod-0.2.1/src/client.rs:92:5
  14: wtf::main::{{closure}}
             at ./src/main.rs:3:18
  15: tokio::runtime::park::CachedParkThread::block_on::{{closure}}
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/runtime/park.rs:285:71
  16: tokio::task::coop::with_budget
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/task/coop/mod.rs:167:5
  17: tokio::task::coop::budget
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/task/coop/mod.rs:133:5
  18: tokio::runtime::park::CachedParkThread::block_on
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/runtime/park.rs:285:31
  19: tokio::runtime::context::blocking::BlockingRegionGuard::block_on
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/runtime/context/blocking.rs:66:14
  20: tokio::runtime::scheduler::multi_thread::MultiThread::block_on::{{closure}}
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/runtime/scheduler/multi_thread/mod.rs:87:22
  21: tokio::runtime::context::runtime::enter_runtime
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/runtime/context/runtime.rs:65:16
  22: tokio::runtime::scheduler::multi_thread::MultiThread::block_on
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/runtime/scheduler/multi_thread/mod.rs:86:9
  23: tokio::runtime::runtime::Runtime::block_on_inner
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/runtime/runtime.rs:358:50
  24: tokio::runtime::runtime::Runtime::block_on
             at /home/arvid/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tokio-1.47.1/src/runtime/runtime.rs:330:18
  25: wtf::main
             at ./src/main.rs:3:57
  26: core::ops::function::FnOnce::call_once
             at /home/arvid/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/ops/function.rs:253:5

The following code snippet reproduces this:

#[tokio::main]
async fn main() {
    let _client = debuginfod::Client::from_env().unwrap();
}

Why is this, and what can I do about it (without forking the library, I tried to look into adding async support, but it would be exceedingly painful to do so without just duplicating all the code in the library to have two versions, and the author is not particularly interested)?

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