`Sourcemap is likely to be incorrect` warnings on `vite build --sourcemap`

Related plugins

• plugin-react

• plugin-react-swc

• plugin-react-oxc

• plugin-rsc

Describe the bug

$ pnpm -C packages/plugin-rsc/examples/starter build --sourcemap

> @vitejs/plugin-rsc-examples-starter@0.0.0 build /home/hiroshi/code/others/vite-plugin-react/packages/plugin-rsc/examples/starter
> vite build --sourcemap

[1/5] analyze client references...
vite v7.3.1 building rsc environment for production...
✓ 55 modules transformed.
[plugin rsc:virtual:vite-rsc/assets-manifest] Sourcemap is likely to be incorrect: a plugin (rsc:virtual:vite-rsc/assets-manifest) was used to transform files, but didn't generate a sourcemap for the transformation. Consult the plugin documentation for help
✓ built in 336ms
[2/5] analyze server references...
vite v7.3.1 building ssr environment for production...
✓ 50 modules transformed.
[plugin rsc:virtual:vite-rsc/assets-manifest] Sourcemap is likely to be incorrect: a plugin (rsc:virtual:vite-rsc/assets-manifest) was used to transform files, but didn't generate a sourcemap for the transformation. Consult the plugin documentation for help
✓ built in 267ms
[3/5] build rsc environment...
vite v7.3.1 building rsc environment for production...
✓ 55 modules transformed.
[plugin vite:reporter] 
(!) /home/hiroshi/code/others/vite-plugin-react/packages/plugin-rsc/examples/starter/src/action.tsx is dynamically imported by virtual:vite-rsc/server-references but also statically imported by /home/hiroshi/code/others/vite-plugin-react/packages/plugin-rsc/examples/starter/src/root.tsx, dynamic import will not move module into another chunk.

[plugin rsc:inject-async-local-storage] Sourcemap is likely to be incorrect: a plugin (rsc:inject-async-local-storage) was used to transform files, but didn't generate a sourcemap for the transformation. Consult the plugin documentation for help
[plugin rsc:inject-async-local-storage] Sourcemap is likely to be incorrect: a plugin (rsc:inject-async-local-storage) was used to transform files, but didn't generate a sourcemap for the transformation. Consult the plugin documentation for help (x2)
[plugin rsc:virtual:vite-rsc/assets-manifest] Sourcemap is likely to be incorrect: a plugin (rsc:virtual:vite-rsc/assets-manifest) was used to transform files, but didn't generate a sourcemap for the transformation. Consult the plugin documentation for help
dist/rsc/assets/react-CHdo91hT.svg    4.13 kB
dist/rsc/assets/index-NeOOZrmx.css    1.40 kB
dist/rsc/index.js                   626.79 kB │ map: 14.28 kB
✓ built in 647ms
[4/5] build client environment...
vite v7.3.1 building client environment for production...
✓ 42 modules transformed.
[plugin rsc:vite-client-raw-import] Sourcemap is likely to be incorrect: a plugin (rsc:vite-client-raw-import) was used to transform files, but didn't generate a sourcemap for the transformation. Consult the plugin documentation for help
dist/client/assets/react-CHdo91hT.svg       4.13 kB │ gzip:  2.05 kB
dist/client/assets/index-NeOOZrmx.css       1.40 kB │ gzip:  0.71 kB
dist/client/assets/entry.rsc-JZAVNEuk.js    0.27 kB │ gzip:  0.24 kB │ map:     0.59 kB
dist/client/assets/index-DPERZMr6.js      222.96 kB │ gzip: 70.55 kB │ map: 1,034.11 kB
✓ built in 478ms
[5/5] build ssr environment...
vite v7.3.1 building ssr environment for production...
✓ 51 modules transformed.
[plugin rsc:virtual:vite-rsc/assets-manifest] Sourcemap is likely to be incorrect: a plugin (rsc:virtual:vite-rsc/assets-manifest) was used to transform files, but didn't generate a sourcemap for the transformation. Consult the plugin documentation for help
[plugin rsc:inject-async-local-storage] Sourcemap is likely to be incorrect: a plugin (rsc:inject-async-local-storage) was used to transform files, but didn't generate a sourcemap for the transformation. Consult the plugin documentation for help
[plugin rsc:inject-async-local-storage] Sourcemap is likely to be incorrect: a plugin (rsc:inject-async-local-storage) was used to transform files, but didn't generate a sourcemap for the transformation. Consult the plugin documentation for help (x2)
[plugin rsc:virtual:vite-rsc/assets-manifest] Sourcemap is likely to be incorrect: a plugin (rsc:virtual:vite-rsc/assets-manifest) was used to transform files, but didn't generate a sourcemap for the transformation. Consult the plugin documentation for help
dist/ssr/assets/entry.rsc-DMKK0oJ_.js      0.54 kB │ map:  0.12 kB
dist/ssr/index.js                      1,560.08 kB │ map: 32.68 kB
✓ built in 745ms

Reproduction

see above

Steps to reproduce

No response

System Info

na

Used Package Manager

npm

Logs

No response

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Make sure this is a Vite issue and not a framework-specific issue.
• Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.
• The provided reproduction is a minimal reproducible example of the bug.

Start by running pnpm -C packages/plugin-rsc/examples/starter build --sourcemap and inspect the plugin-rsc transformations named in the output: virtual:vite-rsc/assets-manifest, inject-async-local-storage, and vite-client-raw-import. Trace the related plugin entry points and compare their transformations with Vite's sourcemap expectations. Done means the reproduced build no longer emits incorrect-sourcemap warnings and the generated maps remain available.