bootstrap: don't resolve symlinks for initial_cargo

[GrigorenkoPV]

I have put the following in my config.toml:

# Includes one of the default files in src/bootstrap/defaults
profile = "compiler"
change-id = 121203

[build]
cargo = "/usr/bin/cargo"
rustc = "/usr/bin/rustc"
rustfmt = "/usr/bin/rustfmt"

I have rustup installed from Arch's repos, which has all of the above paths be symlinks to /usr/bin/rustup. This works just fine with the argv[0] trick that rustup uses.

However, bootstrap resolves symlinks to check whether cargo exists and then uses the resolved path, so it ends up calling rustup directly expecting it to behave like cargo. Which it doesn't.

This PR removes the canonicalization step, in turn fixing the issue, but sacrificing a pretty error message. However, this exact thing is checked by x.py in advance, so I hope it is not a big deal?

[rustbot]

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[rustbot]

This PR modifies src/bootstrap/src/core/config.

If appropriate, please update CONFIG_CHANGE_HISTORY in src/bootstrap/src/utils/change_tracker.rs.

[onur-ozkan]

Stopping bootstrapping on the invalid configuration is actually quite useful (so people doesn't waste time on building when configuration is invalid). I would rather change this validation to be running a simple cargo command and checking if it's working or not. With this approach, your usecase should be working just fine and we can keep validating the initial cargo.

[onur-ozkan]

r? onur-ozkan

[GrigorenkoPV]

@rustbot review

[bors]

☔ The latest upstream changes (presumably #121400) made this pull request unmergeable. Please resolve the merge conflicts.

[onur-ozkan]

Oh, this fixes a bug. Thanks :)

[onur-ozkan]

I will take this to the merge queue once it's been rebased and the commits have been squashed/unified. Having the first commit no longer makes sense.

[onur-ozkan]

@bors r+

[bors]

📌 Commit c42057f has been approved by onur-ozkan

It is now in the queue for this repository.

[bors]

⌛ Testing commit c42057f with merge 71ff1c6...

[bors]

☀️ Test successful - checks-actions
Approved by: onur-ozkan
Pushing 71ff1c6 to master...

[rust-timer]

Finished benchmarking commit (71ff1c6): comparison URL.

Overall result: ✅ improvements - 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
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-5.1%	[-5.1%, -5.1%]	1
All ❌✅ (primary)	-	-	0

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)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-5.1%	[-5.4%, -4.9%]	2
All ❌✅ (primary)	-	-	0

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
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-2.4%	[-3.7%, -1.6%]	13
All ❌✅ (primary)	-	-	0

Binary size

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

Bootstrap: 651.286s -> 650.172s (-0.17%)
Artifact size: 310.96 MiB -> 310.96 MiB (-0.00%)

[GrigorenkoPV]

Thank you a lot for the review and the feedback!

Really appreciate it ❤️