error: internal compiler error: compiler/rustc_middle/src/ty/sty.rs:847:21: expected type for param #0

[yegawong]

Code

struct SqueneceBuffer<'a, T>
where
    &'a T: IntoIterator<Item = &'a u8>,
{
    iter: <&'a T as IntoIterator>::IntoIter,
}

impl<'a, T> SqueneceBuffer<'a, T>
where
    &'a T: IntoIterator<Item = &'a u8>,
{
    fn new(sq: &'a T) -> Self {
        Self {
            iter: sq.into_iter(),
        }
    }

    fn get(&mut self) -> Option<&'a u8> {
        self.iter.next()
    }
}

#[allow(dead_code)]
pub struct Helper<'a, T>
where
    &'a T: IntoIterator<Item = &'a u8>,
{
    buf: SqueneceBuffer<'a, T>,
    unit: u8,
    num: u8,
    used_bit: u8,
}

#[allow(dead_code)]
impl<'a, T> Helper<'a, T>
where
    &'a T: IntoIterator<Item = &'a u8>,
{
    pub fn new(sq: &'a T) -> Self {
        let mut result = Self {
            buf: SqueneceBuffer::new(sq),
            unit: 8,
            num: 0,
            used_bit: 0,
        };
        match result.update() {
            true => result,
            _ => panic!("the squenece can not be empty!"),
        }
    }

    fn update(&mut self) -> bool {
        let nop = self.buf.get();
        match nop {
            Some(n) => {
                self.num = *n;
                self.used_bit = 0;
                true
            }
            _ => false,
        }
    }

    pub fn set_unit(&mut self, u: u8) {
        if u > 32 || u == 0 {
            panic!("the unit can neither be greater than 32 nor 0")
        }
        self.unit = u;
    }

    pub fn get_num_by_bit(&mut self, bit: u8) -> GetResult {
        if bit > 32 || bit == 0 {
            return GetResult::Error;
        }
        let mut rest_bit = 8 - self.used_bit;
        if rest_bit == 0 {
            if self.update() {
                rest_bit = 8
            } else {
                return GetResult::Fail;
            }
        }
        let diff: i8 = bit as i8 - rest_bit as i8;
        if diff <= 0 {
            let num: u32 = (((0xff as u8 >> self.used_bit) & self.num) >> -diff as u8) as u32;
            self.used_bit += bit;
            return GetResult::Whole(num);
        }
        let mut slice: [Option<u8>; 4] = [None; 4];
        slice[0] = Some((0xff as u8 >> self.used_bit) & self.num);
        let mut result: u32 = slice[0].unwrap() as u32;
        let mut bits = rest_bit;
        let exp_bytes: u8 = (diff / 8) as u8;
        let exp_bits: u8 = (diff % 8) as u8;
        let mut i: u8 = 1;
        while i <= exp_bytes {
            if self.update() == false {
                break;
            }
            slice[i as usize] = Some(self.num);
            i += 1;
        }
        for j in &slice[1..] {
            match j {
                Some(n) => {
                    result = (result << 8) + *n as u32;
                    bits += 8;
                }
                _ => break,
            }
        }
        self.used_bit = 8;
        if i <= exp_bytes {
            return GetResult::Semi(result, bits);
        }
        if exp_bits == 0 {
            return GetResult::Whole(result);
        }
        if !self.update() {
            return GetResult::Semi(result, bits);
        }
        result = (result << exp_bits as u32) + (self.num >> (8 - exp_bits as u32) as u8) as u32;
        self.used_bit = exp_bits;
        return GetResult::Whole(result);
    }
}

#[allow(dead_code)]
#[derive(Debug)]
pub enum GetResult {
    Whole(u32),
    Semi(u32, u8),
    Fail,
    Error,
}

// bug!!!
pub struct BitReaderWrapper<T>(T);

impl<'a, T> IntoIterator for &'a BitReaderWrapper<T> 
where
    &'a T: IntoIterator<Item = &'a u8>,
{
    type Item = u32;

    type IntoIter = Helper<'a, T>;

    fn into_iter(self) -> Self::IntoIter {
        Helper::new(&self.0)
    }
}

impl<'a, T> Iterator for Helper<'a, T>
where
    &'a T: IntoIterator<Item = &'a u8>,
{
    type Item = u32;

    fn next(&mut self) -> Option<Self::Item> {
        match self.get_num_by_bit(self.unit) {
            GetResult::Error => panic!("can not read the data"),
            GetResult::Semi(result, _) => Some(result),
            GetResult::Whole(result) => Some(result),
            _ => None
        }
    }
}

fn main() {}

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### Tasks
- [ ] error: internal compiler error: compiler/rustc_middle/src/ty/sty.rs:847:21: expected type for param #0.

rustc --version --verbose:

rustc 1.68.2 (9eb3afe9e 2023-03-27)
binary: rustc
commit-hash: 9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0
commit-date: 2023-03-27
host: x86_64-unknown-linux-gnu
release: 1.68.2
LLVM version: 15.0.6

Error output

error: internal compiler error: compiler/rustc_middle/src/ty/sty.rs:847:21: expected type for param #0 in [ReErased, BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<BitReaderWrapper<_>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>]

thread 'rustc' panicked at 'Box<dyn Any>', /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/compiler/rustc_errors/src/lib.rs:1609:9
stack backtrace:
   0:     0x7f784d9ac59a - std::backtrace_rs::backtrace::libunwind::trace::ha271a8a7e1f3d4ef
                               at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7f784d9ac59a - std::backtrace_rs::backtrace::trace_unsynchronized::h85739da0352c791a
                               at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   ......
 969:     0x7f784d9b9823 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h3205ec2d7fc232c5
                               at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/alloc/src/boxed.rs:1988:9
 970:     0x7f784d9b9823 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h3bb5daec8177f56b
                               at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/alloc/src/boxed.rs:1988:9
 971:     0x7f784d9b9823 - std::sys::unix::thread::Thread::new::thread_start::had7b8061e306bb5c
                               at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/sys/unix/thread.rs:108:17
 972:     0x7f784d871609 - start_thread
                               at /build/glibc-SzIz7B/glibc-2.31/nptl/pthread_create.c:477:8
 973:     0x7f784d794133 - clone
                               at /build/glibc-SzIz7B/glibc-2.31/misc/../sysdeps/unix/sysv/linux/x86_64/clone.S:95
 974:                0x0 - <unknown>

Backtrace

query stack during panic:
#0 [typeck] type-checking `<impl at src/main.rs:39:1: 39:26>::new`
#1 [typeck_item_bodies] type-checking all item bodies
#2 [analysis] running analysis passes on this crate
end of query stack
thread 'rustc' panicked at 'Box<dyn Any>', /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/compiler/rustc_errors/src/lib.rs:1609:9
stack backtrace:
   0:     0x7f784d9ac59a - std::backtrace_rs::backtrace::libunwind::trace::ha271a8a7e1f3d4ef
                               at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/../../backtrace/src/backtrace/libunwind.rs:93:5
   1:     0x7f784d9ac59a - std::backtrace_rs::backtrace::trace_unsynchronized::h85739da0352c791a
                               at /rustc/9eb3afe9ebe9c7d2b84b71002d44f4a0edac95e0/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
  ......
 970:     0x7f784d794133 - clone
                               at /build/glibc-SzIz7B/glibc-2.31/misc/../sysdeps/unix/sysv/linux/x86_64/clone.S:95
 971:                0x0 - <unknown>

[compiler-errors]

Minimized via cargo minimize and some manual item deletion:

struct SeqBuffer<'a, T>
where
    &'a T: IntoIterator<Item = &'a u8>,
{
    iter: <&'a T as IntoIterator>::IntoIter,
}

struct Helper<'a, T>
where
    &'a T: IntoIterator<Item = &'a u8>,
{
    buf: SeqBuffer<'a, T>,
}

impl<'a, T> Helper<'a, T>
where
    &'a T: IntoIterator<Item = &'a u8>,
{
    fn new(sq: &'a T) -> Self {
        loop {}
    }
}

struct BitReaderWrapper<T>(T);

impl<'a, T> IntoIterator for &'a BitReaderWrapper<T>
where
    &'a T: IntoIterator<Item = &'a u8>,
{
    type Item = u32;

    type IntoIter = Helper<'a, T>;

    fn into_iter(self) -> Self::IntoIter {
        Helper::new(&self.0)
    }
}

I can take a quick look into this one I guess.

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