cargo clippy --fix suggesting incorrect code #16654
Description
Summary
I was trying to run cargo clippy --fix and it failed due to it generating incorrect code. The message told me to create an issue so here I am.
/Documents/Stuff/Dev/Ensemble-Emulator/core copilot/prep..-publication >1 !1 > cargo clippy -p monsoon-cli --fix node system 21:50:32
Checking monsoon-cli v0.1.0 (/home/emily/Documents/Stuff/Dev/Ensemble-Emulator/cli)
warning: failed to automatically apply fixes suggested by rustc to crate `monsoon_cli`
after fixes were automatically applied the compiler reported errors within these files:
* cli/src/cli/execution.rs
This likely indicates a bug in either rustc or cargo itself,
and we would appreciate a bug report! You're likely to see
a number of compiler warnings after this message which cargo
attempted to fix but failed. If you could open an issue at
https://github.com/rust-lang/rust-clippy/issues
quoting the full output of this command we'd be very appreciative!
Note that you may be able to make some more progress in the near-term
fixing code with the `--broken-code` flag
The following errors were reported:
error[E0308]: mismatched types
--> cli/src/cli/execution.rs:121:22
|
119 | / if let Ok(cond) = cond {
120 | | res.push(cond)
121 | | } else { cond? }
| |______________________^^^^^_- expected this to be `()`
| |
| expected `()`, found `StopCondition`
|
help: consider using a semicolon here
|
121 | } else { cond?; }
| +
help: consider using a semicolon here
|
121 | } else { cond? };
| +
error: aborting due to 1 previous error
For more information about this error, try `rustc --explain E0308`.
Original diagnostics will follow.
warning: this block may be rewritten with the `?` operator
--> cli/src/cli/execution.rs:121:20
|
121 | } else if let Err(cond) = cond {
| ____________________^
122 | | return Err(cond)
123 | | }
| |_____________^ help: replace it with: `{ cond? }`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#question_mark
= note: `#[warn(clippy::question_mark)]` on by default
warning: `monsoon-cli` (lib) generated 1 warning (run `cargo clippy --fix --lib -p monsoon-cli -- --no-deps` to apply 1 suggestion)
Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.86sThe code responsible for this behavior is this:
/// A stop condition that can be checked during execution
#[derive(Debug, Clone)]
pub enum StopCondition {
/// Stop after N master cycles
Cycles(u128),
/// Stop after N frames
Frames(u64),
/// Stop when PC reaches address (breakpoint)
PcEquals(u16),
/// Stop when opcode is executed
Opcode(u8),
/// Stop when memory address equals value
MemoryEquals {
addr: u16,
value: u8,
and: Option<Box<StopCondition>>,
},
/// Stop when memory address does not equal value
MemoryNotEquals {
addr: u16,
value: u8,
and: Option<Box<StopCondition>>,
},
/// Stop on HLT instruction
OnHalt,
/// Breakpoint at address (alias for PcEquals, kept for backward compatibility)
Breakpoint(u16),
/// Watch memory address for access
MemoryWatch {
addr: u16,
access_type: MemoryAccessType,
},
}
impl StopCondition {
/// Parse a memory condition string like "0x6000==0x80" or "0x6000!=0x00"
pub fn parse_memory_condition(vec: &Vec<String>) -> Result<Vec<StopCondition>, String> {
let mut res = Vec::new();
for s in vec {
let cond: Result<StopCondition, String> = Self::parse_single_condition(s);
if let Ok(cond) = cond {
res.push(cond)
} else if let Err(cond) = cond {
return Err(cond);
}
}
Ok(res)
}
pub fn parse_single_condition(s: &String) -> Result<Self, String> {
if let Some((cond1, cond2)) = s.split_once("&&") {
let cond1 = Self::parse_single_condition(&cond1.to_string());
let cond2 = Self::parse_single_condition(&cond2.to_string());
if let (Ok(cond1), Ok(cond2)) = (cond1, cond2) {
match cond1 {
StopCondition::MemoryEquals {
addr,
value,
..
} => {
return Ok(StopCondition::MemoryEquals {
addr,
value,
and: Some(Box::new(cond2)),
});
}
StopCondition::MemoryNotEquals {
addr,
value,
..
} => {
return Ok(StopCondition::MemoryNotEquals {
addr,
value,
and: Some(Box::new(cond2)),
});
}
_ => {}
}
}
}
if let Some((addr_str, val_str)) = s.split_once("==") {
let addr = parse_hex_u16(addr_str.trim())?;
let value = parse_hex_u8(val_str.trim())?;
Ok(StopCondition::MemoryEquals {
addr,
value,
and: None,
})
} else if let Some((addr_str, val_str)) = s.split_once("!=") {
let addr = parse_hex_u16(addr_str.trim())?;
let value = parse_hex_u8(val_str.trim())?;
Ok(StopCondition::MemoryNotEquals {
addr,
value,
and: None,
})
} else {
Err(format!(
"Invalid memory condition '{}'. Expected format: ADDR==VALUE or ADDR!=VALUE",
s
))
}
}
}Version
rustc 1.95.0-nightly (3a70d0349 2026-02-27)
binary: rustc
commit-hash: 3a70d0349fa378a10c3748f1a48742e61505020f
commit-date: 2026-02-27
host: x86_64-unknown-linux-gnu
release: 1.95.0-nightly
LLVM version: 22.1.0