Fix leaks from panics in destructors

[matthewjasper]

Resurrects #78373.

This avoids the problem with #80949 by not unscheduling drops of function arguments until after the call (so they still get a drop terminator on the function unwind path).

Closes #47949

r? @lcnr

[rustbot]

Some changes occurred in match lowering

cc @Nadrieril

[lcnr]

@bors try @rust-timer queue

r? @pnkfelix (as you've reviewed #78373 3 years ago :3) am looking through these changes myself but would like you to also take a look

[bors]

⌛ Trying commit 28ac9be with merge 1c34390...

[lcnr]

Went through it and mostly understand this PR, am very much not comfortable enough to approve it myself 😅

Thanks @matthewjasper for picking this up again ❤️ really happy about this

[bors]

☀️ Try build successful - checks-actions
Build commit: 1c34390 (1c343902c7b4004d4dcdeb3cc93fcdd886e21595)

[rust-timer]

Finished benchmarking commit (1c34390): comparison URL.

Overall result: ❌ regressions - ACTION NEEDED

Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please fix the regressions and do another perf run. If the next run shows neutral or positive results, the label will be automatically removed.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	1.5%	[0.3%, 12.1%]	245
Regressions ❌ (secondary)	38.2%	[0.3%, 723.1%]	156
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	1.5%	[0.3%, 12.1%]	245

Max RSS (memory usage)

Results (primary -1.8%, secondary -4.0%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	2.8%	[0.8%, 5.9%]	7
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-2.7%	[-8.7%, -0.9%]	36
Improvements ✅ (secondary)	-4.0%	[-6.0%, -2.2%]	28
All ❌✅ (primary)	-1.8%	[-8.7%, 5.9%]	43

Cycles

Results (primary 2.4%, secondary 73.0%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	2.4%	[0.9%, 6.3%]	48
Regressions ❌ (secondary)	73.0%	[1.2%, 281.7%]	33
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	2.4%	[0.9%, 6.3%]	48

Binary size

Results (primary 1.1%, secondary 1.3%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	1.1%	[0.0%, 4.9%]	136
Regressions ❌ (secondary)	1.3%	[0.1%, 7.7%]	91
Improvements ✅ (primary)	-0.1%	[-0.1%, -0.1%]	2
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	1.1%	[-0.1%, 4.9%]	138

Bootstrap: 673.596s -> 675.825s (0.33%)
Artifact size: 318.88 MiB -> 311.92 MiB (-2.19%)

[matthewjasper]

@bors try @rust-timer queue

[craterbot]

🎉 Experiment pr-125923 is completed!
📊 270 regressed and 1 fixed (474099 total)
📰 Open the full report.

⚠️ If you notice any spurious failure please add them to the blacklist!
ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[matthewjasper]

Looks like there's a bug somewhere (failures are ICEs)

[bors]

☔ The latest upstream changes (presumably #126784) made this pull request unmergeable. Please resolve the merge conflicts.

[matthewjasper]

@bors try

[bors]

⌛ Trying commit 5c356c7 with merge 8585d8c...

[bors]

☀️ Try build successful - checks-actions
Build commit: 8585d8c (8585d8c57bfa6d7d66340412e06b5611fa79cc61)

[matthewjasper]

@craterbot check

[craterbot]

👌 Experiment pr-125923-1 created and queued.
🤖 Automatically detected try build 8585d8c
🔍 You can check out the queue and this experiment's details.

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[rust-timer]

Finished benchmarking commit (8585d8c): comparison URL.

Overall result: ❌ regressions - ACTION NEEDED

Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please fix the regressions and do another perf run. If the next run shows neutral or positive results, the label will be automatically removed.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	1.1%	[0.2%, 3.6%]	135
Regressions ❌ (secondary)	1.6%	[0.2%, 7.1%]	48
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.5%	[-0.9%, -0.3%]	5
All ❌✅ (primary)	1.1%	[0.2%, 3.6%]	135

Max RSS (memory usage)

Results (primary 2.9%, secondary -0.7%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	3.5%	[1.3%, 8.2%]	11
Regressions ❌ (secondary)	4.1%	[4.1%, 4.1%]	1
Improvements ✅ (primary)	-3.6%	[-3.6%, -3.6%]	1
Improvements ✅ (secondary)	-5.5%	[-5.5%, -5.5%]	1
All ❌✅ (primary)	2.9%	[-3.6%, 8.2%]	12

Cycles

Results (primary 1.9%, secondary 3.7%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	1.9%	[0.7%, 4.1%]	55
Regressions ❌ (secondary)	4.2%	[1.1%, 7.4%]	15
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-4.4%	[-4.4%, -4.4%]	1
All ❌✅ (primary)	1.9%	[0.7%, 4.1%]	55

Binary size

Results (primary 1.1%, secondary 1.3%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	1.1%	[0.0%, 4.9%]	138
Regressions ❌ (secondary)	1.3%	[0.1%, 7.7%]	91
Improvements ✅ (primary)	-0.0%	[-0.0%, -0.0%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	1.1%	[-0.0%, 4.9%]	139

Bootstrap: 693.722s -> 697.127s (0.49%)
Artifact size: 326.71 MiB -> 327.43 MiB (0.22%)

[craterbot]

🚧 Experiment pr-125923-1 is now running

ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[pnkfelix]

Finally got around to making a pernos.co run with and without this PR in place, to aid me to inpsect a fine-grained trace of its behavior.

• Without PR: link
• With PR: link

[craterbot]

🎉 Experiment pr-125923-1 is completed!
📊 19 regressed and 8 fixed (475963 total)
📰 Open the full report.

⚠️ If you notice any spurious failure please add them to the blacklist!
ℹ️ Crater is a tool to run experiments across parts of the Rust ecosystem. Learn more

[pnkfelix]

I still haven't had a chance to give this a proper review, and I am about to go on vacation for a week.

So I'm going to re-roll the review. If it doesn't get reviewed within ten days, feel free to re-assign it to me again.

r? compiler-team