Code coverage reports wrong count of loop header

A simple test of the -C instrument-coverage feature returns the wrong count (9 instead of 10) of the loop header on line 4 when built with Rust 1.93.0:

main.rs:

fn main(){
    let mut sum: u32 = 0;

    for i in 1..10 {
        sum += i;
    }

    if false{
        println!("This code can't be reached");
    }
    println!("Sum: {}", sum);
}

Reproducer:

rustc -C instrument-coverage main.rs -o main
LLVM_PROFILE_FILE='testprof.profraw' ./main
llvm-profdata merge -sparse testprof.profraw -o testprof.profdata
llvm-cov show  main -instr-profile=testprof.profdata > coverage.out

This test works as expected with 1.92.0.

Meta

$ rustc +1.93.0 --version
rustc 1.93.0 (254b59607 2026-01-19)

Start with the main.rs reproducer and run the listed rustc, LLVM_PROFILE_FILE, llvm-profdata, and llvm-cov commands under Rust 1.93.0, then repeat with 1.92.0. Compare coverage.out, focusing on the loop header on line 4; done means the 1.93.0 report counts it as 10 rather than 9.