Small fixes for --crate-type staticlib

[bjorn3]

The first commit doesn't have an effect until we start translating error messages. The second commit fixes potential linker errors when combining --crate-type staticlib with another crate type and I think -Cprefer-dynamic.

[rustbot]

r? @wesleywiser

(rustbot has picked a reviewer for you, use r? to override)

[rustbot]

rustc_error_messages was changed

cc @davidtwco, @compiler-errors, @JohnTitor, @estebank, @TaKO8Ki

[wesleywiser]

Thanks @bjorn3!

@bors r+

[bors]

📌 Commit ed77a61 has been approved by wesleywiser

It is now in the queue for this repository.

[bors]

⌛ Testing commit ed77a61 with merge aaeecca1456e1f5d90a3f5e2cb56686816f3a287...

[bors]

💔 Test failed - checks-actions

[bjorn3]

I didn't account for it being possible for a crate to have 0 crate types like would happen if you use --crate-type cdylib on a platform not supporting cdylib's.

[wesleywiser]

@bors r+

[bors]

📌 Commit 7705116 has been approved by wesleywiser

It is now in the queue for this repository.

[bors]

⌛ Testing commit 7705116 with merge d9e317a...

[bors]

☀️ Test successful - checks-actions
Approved by: wesleywiser
Pushing d9e317a to master...

[rust-timer]

Finished benchmarking commit (d9e317a): 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)

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

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)	1.0%	[1.0%, 1.1%]	2
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	1.0%	[1.0%, 1.1%]	2