Fix test and update external-block ABIs

Author: gnzlbg

src/items/external-blocks.md

@@ -85,12 +85,12 @@ There are also some platform-specific ABI strings:
 * `extern "vectorcall"` -- The `vectorcall` ABI -- corresponds to MSVC's
   `__vectorcall` and clang's `__attribute__((vectorcall))`
 
-Finally, there are some rustc-specific ABI strings:
+Finally, there are some unstable rustc-specific ABI strings:
 
-* `extern "rust-intrinsic"` -- The ABI of rustc intrinsics.
-* `extern "rust-call"` -- The ABI of the Fn::call trait functions.
-* `extern "platform-intrinsic"` -- Specific platform intrinsics -- like, for
-  example, `sqrt` -- have this ABI. You should never have to deal with it.
+* `extern "rust-intrinsic"` -- The ABI of rustc intrinsics, equivalent to `"Rust"`.
+* `extern "rust-call"` -- The ABI of the Fn::call trait functions, equivalent to `"Rust"`.
+* `extern "platform-intrinsic"` -- The ABI of Specific platform intrinsics, equivalent to `"Rust"` -- like, for
+  example, `sqrt` -- equivalent to `"Rust"`. You should never have to deal with it.
 
 ## Variadic functions
 

src/items/functions.md

@@ -112,7 +112,7 @@ sufficient context to determine the type parameters. For example,
 Extern function _definitions_ allow defining functions that can be called 
 with a particular ABI:
 
-```rust,no_run
+```rust,ignore
 extern "ABI" fn foo() { ... }
 ```
 
@@ -173,8 +173,9 @@ equivalent to the `"Rust"` ABI, e.g.,
 [`"rust-intrinsic"`](https://doc.rust-lang.org/unstable-book/language-features/intrinsics.html?highlight=rust-intrin#intrinsics)
 or
 [`"platform-intrinsic"`](https://doc.rust-lang.org/unstable-book/language-features/platform-intrinsics.html).
-Refer to the [Unstable Book](https://doc.rust-lang.org/unstable-book) for more
-information about these.
+For more information about these refer to the [ABI section of external block
+items][external-blocks.md#ABI] and the [Unstable
+Book](https://doc.rust-lang.org/unstable-book).
 
 ## Const functions