Emit ForbiddenBound fatally

[mu001999]

Bounds in binders are denied, hir items won't contain and index them. But nested items in the bounds will still be lowered to hir. And their parents, i.e., the block in bounds is not in hir. So that ICE happens when error handling requires visiting hir parents.

I think fixing this by aborting immediately when meeting bounds in binders is good enough.

Fixes #149695

[rustbot]

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[rust-log-analyzer]

The job aarch64-gnu-llvm-20-1 failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

---- [ui] tests/ui/higher-ranked/higher-lifetime-bounds.rs stdout ----
Saved the actual stderr to `/checkout/obj/build/aarch64-unknown-linux-gnu/test/ui/higher-ranked/higher-lifetime-bounds/higher-lifetime-bounds.stderr`
diff of stderr:

4 LL |     f: for<'xa, 'xb: 'xa+'xa> fn(&'xa i32, &'xb i32) -> &'xa i32)
5    |                      ^^^ ^^^
6 
- error: bounds cannot be used in this context
-   --> $DIR/higher-lifetime-bounds.rs:16:34
-    |
- LL | fn bar2<'a, 'b, F: for<'xa, 'xb: 'xa> Fn(&'xa i32, &'xb i32) -> &'xa i32>(
-    |                                  ^^^
- 
- error: bounds cannot be used in this context
-   --> $DIR/higher-lifetime-bounds.rs:31:28
-    |
- LL |     where F: for<'xa, 'xb: 'xa> Fn(&'xa i32, &'xb i32) -> &'xa i32
-    |                            ^^^
- 
- error: bounds cannot be used in this context
-   --> $DIR/higher-lifetime-bounds.rs:43:25
-    |
- LL |     where for<'xa, 'xb: 'xa> F: Fn(&'xa i32, &'xb i32) -> &'xa i32
-    |                         ^^^
- 
- error: bounds cannot be used in this context
-   --> $DIR/higher-lifetime-bounds.rs:51:28
-    |
- LL | struct S1<F: for<'xa, 'xb: 'xa> Fn(&'xa i32, &'xb i32) -> &'xa i32>(F);
-    |                            ^^^
- 
- error: bounds cannot be used in this context
-   --> $DIR/higher-lifetime-bounds.rs:53:40
-    |
- LL | struct S2<F>(F) where F: for<'xa, 'xb: 'xa> Fn(&'xa i32, &'xb i32) -> &'xa i32;
-    |                                        ^^^
- 
- error: bounds cannot be used in this context
-   --> $DIR/higher-lifetime-bounds.rs:55:37
-    |
- LL | struct S3<F>(F) where for<'xa, 'xb: 'xa> F: Fn(&'xa i32, &'xb i32) -> &'xa i32;
-    |                                     ^^^
- 
- error: bounds cannot be used in this context
-   --> $DIR/higher-lifetime-bounds.rs:58:29
-    |
- LL | struct S_fnty(for<'xa, 'xb: 'xa> fn(&'xa i32, &'xb i32) -> &'xa i32);
-    |                             ^^^
- 
- error: bounds cannot be used in this context
-   --> $DIR/higher-lifetime-bounds.rs:61:33
-    |
- LL | type T1 = Box<dyn for<'xa, 'xb: 'xa> Fn(&'xa i32, &'xb i32) -> &'xa i32>;
-    |                                 ^^^
- 
- error: bounds cannot be used in this context
-   --> $DIR/higher-lifetime-bounds.rs:65:34
-    |
- LL |     let _ : Option<for<'xa, 'xb: 'xa> fn(&'xa i32, &'xb i32) -> &'xa i32> = None;
-    |                                  ^^^
- 
- error: bounds cannot be used in this context
-   --> $DIR/higher-lifetime-bounds.rs:67:42
-    |
- LL |     let _ : Option<Box<dyn for<'xa, 'xb: 'xa> Fn(&'xa i32, &'xb i32) -> &'xa i32>> = None;
-    |                                          ^^^
- 
- error: aborting due to 11 previous errors
+ error: aborting due to 1 previous error
68 
---
To only update this specific test, also pass `--test-args higher-ranked/higher-lifetime-bounds.rs`

error: 1 errors occurred comparing output.
status: exit status: 1
command: env -u RUSTC_LOG_COLOR RUSTC_ICE="0" RUST_BACKTRACE="short" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/tests/ui/higher-ranked/higher-lifetime-bounds.rs" "-Zthreads=1" "-Zsimulate-remapped-rust-src-base=/rustc/FAKE_PREFIX" "-Ztranslate-remapped-path-to-local-path=no" "-Z" "ignore-directory-in-diagnostics-source-blocks=/cargo" "-Z" "ignore-directory-in-diagnostics-source-blocks=/checkout/vendor" "--sysroot" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2" "--target=aarch64-unknown-linux-gnu" "--check-cfg" "cfg(test,FALSE)" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "-Zwrite-long-types-to-disk=no" "-Cstrip=debuginfo" "--emit" "metadata" "-C" "prefer-dynamic" "--out-dir" "/checkout/obj/build/aarch64-unknown-linux-gnu/test/ui/higher-ranked/higher-lifetime-bounds" "-A" "unused" "-W" "unused_attributes" "-A" "internal_features" "-A" "unused_parens" "-A" "unused_braces" "-Crpath" "-Cdebuginfo=0" "-Lnative=/checkout/obj/build/aarch64-unknown-linux-gnu/native/rust-test-helpers"
stdout: none
--- stderr -------------------------------
error: bounds cannot be used in this context
##[error]  --> /checkout/tests/ui/higher-ranked/higher-lifetime-bounds.rs:8:22
   |
LL |     f: for<'xa, 'xb: 'xa+'xa> fn(&'xa i32, &'xb i32) -> &'xa i32)
   |                      ^^^ ^^^

error: aborting due to 1 previous error
------------------------------------------

---- [ui] tests/ui/higher-ranked/higher-lifetime-bounds.rs stdout end ----
---- [ui] tests/ui/higher-ranked/higher-ranked-invalid-bounds.rs stdout ----
Saved the actual stderr to `/checkout/obj/build/aarch64-unknown-linux-gnu/test/ui/higher-ranked/higher-ranked-invalid-bounds/higher-ranked-invalid-bounds.stderr`
diff of stderr:

4 LL | type A = for<'b, 'a: 'b> fn();
5    |                      ^^
6 
- error: bounds cannot be used in this context
-   --> $DIR/higher-ranked-invalid-bounds.rs:4:22
-    |
- LL | type B = for<'b, 'a: 'b,> fn();
-    |                      ^^
+ error: aborting due to 1 previous error
12 
- error: bounds cannot be used in this context
-   --> $DIR/higher-ranked-invalid-bounds.rs:5:22
-    |
- LL | type C = for<'b, 'a: 'b +> fn();
-    |                      ^^
- 
- error[E0658]: only lifetime parameters can be used in this context
-   --> $DIR/higher-ranked-invalid-bounds.rs:6:18
-    |
- LL | type D = for<'a, T> fn();
-    |                  ^
-    |
-    = note: see issue #108185 <https://github.com/rust-lang/rust/issues/108185> for more information
-    = help: add `#![feature(non_lifetime_binders)]` to the crate attributes to enable
-    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
- 
- error[E0658]: only lifetime parameters can be used in this context
-   --> $DIR/higher-ranked-invalid-bounds.rs:7:18
-    |
- LL | type E = dyn for<T, U> Fn();
-    |                  ^  ^
-    |
-    = note: see issue #108185 <https://github.com/rust-lang/rust/issues/108185> for more information
-    = help: add `#![feature(non_lifetime_binders)]` to the crate attributes to enable
-    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
- 
- error: aborting due to 5 previous errors
- 
- For more information about this error, try `rustc --explain E0658`.
42 
---
To only update this specific test, also pass `--test-args higher-ranked/higher-ranked-invalid-bounds.rs`

error: 1 errors occurred comparing output.
status: exit status: 1
command: env -u RUSTC_LOG_COLOR RUSTC_ICE="0" RUST_BACKTRACE="short" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2/bin/rustc" "/checkout/tests/ui/higher-ranked/higher-ranked-invalid-bounds.rs" "-Zthreads=1" "-Zsimulate-remapped-rust-src-base=/rustc/FAKE_PREFIX" "-Ztranslate-remapped-path-to-local-path=no" "-Z" "ignore-directory-in-diagnostics-source-blocks=/cargo" "-Z" "ignore-directory-in-diagnostics-source-blocks=/checkout/vendor" "--sysroot" "/checkout/obj/build/aarch64-unknown-linux-gnu/stage2" "--target=aarch64-unknown-linux-gnu" "--check-cfg" "cfg(test,FALSE)" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "-Zwrite-long-types-to-disk=no" "-Cstrip=debuginfo" "--emit" "metadata" "-C" "prefer-dynamic" "--out-dir" "/checkout/obj/build/aarch64-unknown-linux-gnu/test/ui/higher-ranked/higher-ranked-invalid-bounds" "-A" "unused" "-W" "unused_attributes" "-A" "internal_features" "-A" "unused_parens" "-A" "unused_braces" "-Crpath" "-Cdebuginfo=0" "-Lnative=/checkout/obj/build/aarch64-unknown-linux-gnu/native/rust-test-helpers"
stdout: none
--- stderr -------------------------------
error: bounds cannot be used in this context
##[error]  --> /checkout/tests/ui/higher-ranked/higher-ranked-invalid-bounds.rs:3:22
   |
LL | type A = for<'b, 'a: 'b> fn(); //~ ERROR bounds cannot be used in this context
   |                      ^^

error: aborting due to 1 previous error
------------------------------------------