`rustc -C help` panics (ICEs) when piped to a closed stdout

### Code

```cmd
rustc -C help | cmd /c exit
```

After more testing, this only reproduces consistently under cmd, as other Windows shells have diverging behavior about what it means to close a pipe via program termination 🙃

`rustc --help | cmd /c exit` *does not* panic, but this appears to be not because of rustc doing anything different, but because `rustc` finishes writing to stdout before it is closed.

### Meta

Note: never occurs under `#[cfg(unix)]`, as rustc sets `SIGPIPE` to `SIG_DFL`.

<details><summary><code>rustc_driver::set_sigpipe_handler</code></summary>

https://github.com/rust-lang/rust/blob/7f08d04d60d03e1a52dae61ce6aa50996898702b/compiler/rustc_driver/src/lib.rs#L433-L440

</details>



`rustc --version --verbose`:
```
rustc 1.63.0-nightly (dc80ca78b 2022-06-21)
binary: rustc
commit-hash: dc80ca78b6ec2b6bba02560470347433bcd0bb3c
commit-date: 2022-06-21
host: x86_64-pc-windows-msvc
release: 1.63.0-nightly
LLVM version: 14.0.5
```

### Error output

```
thread 'main' panicked at 'failed printing to stdout: The pipe is being closed. (os error 232)', library\std\src\io\stdio.rs:1015:9

error: internal compiler error: unexpected panic

note: the compiler unexpectedly panicked. this is a bug.

note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md

note: rustc 1.63.0-nightly (dc80ca78b 2022-06-21) running on x86_64-pc-windows-msvc

note: compiler flags: -C help

query stack during panic:
end of query stack
```


<details><summary><strong>Backtrace</strong></summary>
<p>

```
stack backtrace:
   0:     0x7ffecbca9dff - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h46bec461e9e7ac22
   1:     0x7ffecbce4a4a - core::fmt::write::h2cf2927a9deb2e17
   2:     0x7ffecbc9c2e9 - <std::io::IoSliceMut as core::fmt::Debug>::fmt::hfd12a4a4f03cb21d
   3:     0x7ffecbcad6eb - std::panicking::default_hook::h22600ff9cff4f04f
   4:     0x7ffecbcad36b - std::panicking::default_hook::h22600ff9cff4f04f
   5:     0x7ffe8f597f06 - rustc_driver[9e128b4dc2b1f3f4]::pretty::print_after_hir_lowering
   6:     0x7ffecbcade92 - std::panicking::rust_panic_with_hook::hf01515033fcb4adb
   7:     0x7ffecbcadc2d - <std::panicking::begin_panic_handler::StrPanicPayload as core::panic::BoxMeUp>::get::h8d0ff84b444c4809
   8:     0x7ffecbcaaa37 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h46bec461e9e7ac22
   9:     0x7ffecbcad909 - rust_begin_unwind
  11:     0x7ffecbc9a185 - std::io::stdio::_print::heedac1eb9faaac98
  12:     0x7ffe8f5a34b3 - rustc_driver[9e128b4dc2b1f3f4]::handle_options
  13:     0x7ffe8f598e68 - <rustc_driver[9e128b4dc2b1f3f4]::RunCompiler>::run
  14:     0x7ffe8f5203be - <rustc_ast_passes[ccae167a3a40ca07]::node_count::NodeCounter as rustc_ast[f496af66d74beb8c]::visit::Visitor>::visit_attribute
  15:     0x7ffe8f5a54fb - rustc_driver[9e128b4dc2b1f3f4]::main
  16:     0x7ff7e017100e - <unknown>
  17:     0x7ff7e0171076 - <unknown>
  18:     0x7ff7e017105c - <unknown>
  19:     0x7ffecbc8c0b1 - std::rt::lang_start_internal::h562b7c63b69fd4a3
  20:     0x7ff7e0171037 - <unknown>
  21:     0x7ff7e0171284 - <unknown>
  22:     0x7fff0f1b54e0 - BaseThreadInitThunk
  23:     0x7fff1130485b - RtlUserThreadStart
```

</p>
</details>

	#[cfg(unix)]
	pub fn set_sigpipe_handler() {
	unsafe {
	// Set the SIGPIPE signal handler, so that an EPIPE
	// will cause rustc to terminate, as expected.
	assert_ne!(libc::signal(libc::SIGPIPE, libc::SIG_DFL), libc::SIG_ERR);
	}
	}

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`rustc -C help` panics (ICEs) when piped to a closed stdout #98700

CAD97
openedon Jun 30, 2022

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rustc -C help panics (ICEs) when piped to a closed stdout #98700

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CAD97openedon Jun 30, 2022