Remove support for compiler plugins.

nnethercote · nnethercote · commit 8eca01f4b6e0 · 2023-11-04T08:50:46.000+11:00
They've been deprecated for four years. This commit includes the following changes. - It eliminates the `rustc_plugin_impl` crate. - It changes the language used for lints in `compiler/rustc_driver_impl/src/lib.rs` and `compiler/rustc_lint/src/context.rs`. External lints are now called "loaded" lints, rather than "plugins" to avoid confusion with the old plugins. This only has a tiny effect on the output of `-W help`. - E0457 and E0498 are no longer used. - E0463 is narrowed, now only relating to unfound crates, not plugins. - The `plugin` feature was moved from "active" to "removed". - It removes the entire plugins chapter from the unstable book. - It removes quite a few tests, mostly all of those in `tests/ui-fulldeps/plugin/`. Closes #29597.
diff --git a/scripts/test_rustc_tests.sh b/scripts/test_rustc_tests.sh
@@ -68,7 +68,6 @@ rm -r tests/run-make/split-debuginfo # same
 rm -r tests/run-make/symbols-include-type-name # --emit=asm not supported
 rm -r tests/run-make/target-specs # i686 not supported by Cranelift
 rm -r tests/run-make/mismatching-target-triples # same
-rm -r tests/run-make/use-extern-for-plugins # same
 rm tests/ui/asm/x86_64/issue-82869.rs # vector regs in inline asm not yet supported
 rm tests/ui/asm/x86_64/issue-96797.rs # const and sym inline asm operands don't work entirely correctly
 
