Fix misleading message in struct repr alignment and packed

[chenyukang]

Fixes #121425

By the way, fix the spans for the argument in the second commit.

[rustbot]

r? @wesleywiser

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[compiler-errors]

just a verb conjugation nit, r=me after!

[compiler-errors]

r? compiler-errors @rustbot author

[chenyukang]

@rustbot r=compiler-errors

[chenyukang]

@bors r=compiler-errors

[bors]

📌 Commit 53dba7f has been approved by compiler-errors

It is now in the queue for this repository.

[bors]

⌛ Testing commit 53dba7f with merge f7cb53e...

[bors]

☀️ Test successful - checks-actions
Approved by: compiler-errors
Pushing f7cb53e to master...

[rust-timer]

Finished benchmarking commit (f7cb53e): comparison URL.

Overall result: no relevant changes - no action needed

@rustbot label: -perf-regression

Instruction count

This benchmark run did not return any relevant results for this metric.

Max RSS (memory usage)

Results

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)	-	-	0
Regressions ❌ (secondary)	1.3%	[0.5%, 2.1%]	2
Improvements ✅ (primary)	-3.1%	[-3.7%, -2.6%]	2
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-3.1%	[-3.7%, -2.6%]	2

Cycles

This benchmark run did not return any relevant results for this metric.

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 643.294s -> 643.541s (0.04%)
Artifact size: 175.02 MiB -> 175.00 MiB (-0.01%)