Anchor Build Fails: proc-macro2 v1.0.95 Compilation Error with Missing Span Methods

[TheLazySol]

Issue:

I just recently decided to utilize some of the Solana Templates for the first time and during the anchor build, the compilation fails with errors related to missing methods in proc-macro2 v1.0.95.

It appears to be a dependency resolution issue where the version of proc-macro2 being pulled in (1.0.95) is incompatible with the version expected by Anchor's macros... though im not sure.

Error Messages

error[E0599]: no method named `file` found for reference `&proc_macro::Span`
error[E0599]: no method named `local_file` found for reference `&proc_macro::Span`

Environment

• Anchor version: 0.31.1
• Solana CLI: 2.1.21 (src:8a085eeb; feat:1416569292, client:Agave)
• proc-macro2 version: 1.0.95
• OS: Linux (WSL2)
• Rust version: 1.87.0

More Details

The error occurs in the proc-macro2 crate's wrapper.rs file, specifically when trying to access file() and local_file() methods on proc_macro::Span. These methods appear to be either:

1. Not available in the current version
2. Behind a feature flag
3. Incompatible with the current version of proc-macro2 being used

Steps to Reproduce

1. Followed the README.md guide to create a new project: pnpm create solana-dapp@latest -t gh:solana-developers/solana-templates/templates/template-next-tailwind-basic
2. Run pnpm install
3. Run pnpm run setup
4. Run pnpm run anchor-build
5. Observe compilation errors related to proc-macro2

---

• Is there a specific version of proc-macro2 that is known to work with the current Anchor version?
• Are there any feature flags that need to be enabled/disabled to resolve this issue?

[TheLazySol]

Same issue occurs in the Legacy template as well.

[beeman]

Thanks for creating the issue @TheLazySol.

Can you verify if this works on your machine with a plain anchor app (anchor init <project>)?

[TheLazySol]

Thanks for creating the issue @TheLazySol.

Can you verify if this works on your machine with a plain anchor app (anchor init <project>)?

@beeman Yes, I was getting the same exact error even with anchor init.

So it is definitely was a me issue. However, I just resolved it.

I had ran mucho install to ensure that my environment wasn't missing anything.

Then I checked to see what versions I had and so I updated them to the following:

• rust/cargo - rustc 1.89.0-nightly (c68340350 2025-06-18)
• nvm - 0.39.7
• node - 22.16.0
• yarn - 1.22.22
• avm - 0.31.1
• anchor - 0.31.1
• solana - 2.1.21

I used these issues to reference the fixes:

• fix: Update proc-macro2 usage for latest nightly #3663
• Anchor 0.31.0 update #326

[TheLazySol]

I will now close this issue. Looks like the main issue was the node version and the rust/cargo version.

[beeman]

Glad you managed to get it working! Mucho is awesome! 👏