regression: MIR assertion failure ICE

[Mark-Simulacrum]

Crater picked up this issue:

• https://crater-reports.s3.amazonaws.com/beta-1.60-1/beta-2022-02-22/gh/playXE.Jazz/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.60-1/beta-2022-02-22/gh/Ahrimanox.strategy_game/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.60-1/beta-2022-02-22/gh/Sonnenhut.aoc2019/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.60-1/beta-2022-02-22/gh/aaronjeline.rvm/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.60-1/beta-2022-02-22/gh/abesto.byote/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.60-1/beta-2022-02-22/gh/comcloudway.blueprint/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.60-1/beta-2022-02-22/gh/hmr.sequoia/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.60-1/beta-2022-02-22/gh/safesoftware.slpkg/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.60-1/beta-2022-02-22/gh/sim82.aoc2019/log.txt
• https://crater-reports.s3.amazonaws.com/beta-1.60-1/beta-2022-02-22/gh/vagicc.block_histories/log.txt

[INFO] [stderr] thread 'rustc' panicked at 'assertion failed: `(left == right)`
[INFO] [stderr]   left: `7`,
[INFO] [stderr]  right: `4`', compiler/rustc_middle/src/mir/mod.rs:500:13
[INFO] [stderr] stack backtrace:

[bjorn3]

This seems to be the assertion in

rust/compiler/rustc_middle/src/mir/mod.rs

Lines 512 to 523 in 0677edc

	/// Returns the source info associated with `location`.
	pub fn source_info(&self, location: Location) -> &SourceInfo {
	let block = &self[location.block];
	let stmts = &block.statements;
	let idx = location.statement_index;
	if idx < stmts.len() {
	&stmts[idx].source_info
	} else {
	assert_eq!(idx, stmts.len());
	&block.terminator().source_info
	}
	}

In other words the statement_index is higher than the actual statement count. I'm guessing an optimization removes statements but doesn't update the source infos.

[Mark-Simulacrum]

@rustbot ping bisect

Can we try to get a bisection for this failure? Any of the repositories above should work (e.g., https://github.com/playXE/Jazz)

[rustbot]

Hey Cleanup Crew ICE-breakers! This bug has been identified as a good
"Cleanup ICE-breaking candidate". In case it's useful, here are some
instructions for tackling these sorts of bugs. Maybe take a look?
Thanks! <3

cc @AminArria @ayazhafiz @camelid @chrissimpkins @contrun @elshize @h-michael @HallerPatrick @hdhoang @hellow554 @henryboisdequin @imtsuki @JamesPatrickGill @kanru @KarlK90 @matheus-consoli @mental32 @nmccarty @Noah-Kennedy @pard68 @PeytonT @pierreN @Redblueflame @RobbieClarken @RobertoSnap @robjtede @SarthakSingh31 @shekohex @sinato @smmalis37 @steffahn @Stupremee @tamuhey @turboladen @woshilapin @yerke

[steffahn]

Seems to be fixed already

[steffahn]

Tested Jazz and slpkg, it’s fixed for both in latest beta; bisections on slpkg:

regression in: 9cdefd7
fixed in: d4de1f2

[Mark-Simulacrum]

Going to go ahead and close then, thanks @steffahn!