Detect misparsed binop caused by missing semi

[estebank]

When encountering

foo()
*bar = baz;

We currently emit potentially two errors, one for the return type of
foo not being multiplicative by the type of bar, and another for
foo() * bar not being assignable.

We now check for this case and suggest adding a semicolon in the right
place and emit only a single error.

Fix #80446.

[rustbot]

r? @davidtwco

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[davidtwco]

r=me with this change

[estebank]

@bors r=davidtwco

[bors]

📌 Commit 4b7aaca has been approved by davidtwco

It is now in the queue for this repository.

[bors]

⌛ Testing commit 4b7aaca with merge fb61292...

[bors]

☀️ Test successful - checks-actions
Approved by: davidtwco
Pushing fb61292 to master...

[rust-timer]

Finished benchmarking commit (fb61292): comparison URL.

Overall result: ❌ regressions - no action needed

@rustbot label: -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)	0.4%	[0.4%, 0.4%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.4%	[0.4%, 0.4%]	1

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)	0.7%	[0.4%, 1.0%]	3
Regressions ❌ (secondary)	2.1%	[0.7%, 3.6%]	2
Improvements ✅ (primary)	-0.9%	[-1.3%, -0.6%]	3
Improvements ✅ (secondary)	-3.4%	[-3.5%, -3.3%]	2
All ❌✅ (primary)	-0.1%	[-1.3%, 1.0%]	6

Cycles

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)	0.4%	[0.4%, 0.4%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.4%	[0.4%, 0.4%]	1

Binary size

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)	0.0%	[0.0%, 0.0%]	3
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.0%	[-0.0%, -0.0%]	2
All ❌✅ (primary)	-	-	0

Bootstrap: 663.447s -> 662.377s (-0.16%)
Artifact size: 308.96 MiB -> 308.98 MiB (0.01%)