Rollup merge of #149501 - lcnr:no-hard-error-on-norm-failure, r=lqd,oli-obk

CTFE: avoid emitting a hard error on generic normalization failures

Fixes rust-lang/rust#149081.

The fix is quite unsatisfying and should not be necessary, cc rust-lang/rust#149283. That change is significantly more involved. This temporary fix introduces some unnecessary complexity and may hide other type system bugs.

cc ````@rust-lang/types```` I think we should try to fix issue rust-lang/rust#149283 in the near future and then remove this hack again.

I originally intended a more targeted fix. I wanted to skip evaluating constants in MIR opts if their body was polymorphic and the current generic arguments still reference generic parameters. Notes from looking into this:
- we only fetch the MIR in the `eval_to_allocation_raw` query
- figuring out which MIR to use is hard
	- dealing with trivial consts is annoying
	- need to resolve instances for associated consts
	- implementing this by hand is hard
- inlining handles this issue by bailing on literally all normalization failures, even the ones that imply an unsoundness
	- `try_normalize_after_erasing_regions` generally does two things
		- deal with ambiguity after inlining
		- deal with error tainting issues (please don't, we should stop doing that)
- CTFE could be changed to always silently ignore normalization failures if we're in a generic body
	- hides actual bugs <- went with this option

r? types
tree: 3f7bf2c196373e3bfaf1d90a5b87c72b53c022f4
  1. .github/
  2. compiler/
  3. library/
  4. LICENSES/
  5. src/
  6. tests/
  7. .clang-format
  8. .editorconfig
  9. .git-blame-ignore-revs
  10. .gitattributes
  11. .gitignore
  12. .gitmodules
  13. .ignore
  14. .mailmap
  15. bootstrap.example.toml
  16. Cargo.lock
  17. Cargo.toml
  18. CODE_OF_CONDUCT.md
  19. configure
  20. CONTRIBUTING.md
  21. COPYRIGHT
  22. INSTALL.md
  23. LICENSE-APACHE
  24. license-metadata.json
  25. LICENSE-MIT
  26. package.json
  27. README.md
  28. RELEASES.md
  29. REUSE.toml
  30. rust-bors.toml
  31. rustfmt.toml
  32. triagebot.toml
  33. typos.toml
  34. x
  35. x.ps1
  36. x.py
  37. yarn.lock
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