… example does

This commit removes a few calls to panic and/or assert in `rust_eh_personality`.
This function definitely can't itself panic (that'd probably segfault or do
something else weird) and I was also noticing that a `pub extern fn foo() {}`
cdylib was abnormally large. Turns out all that size was the panicking machinery
brought in by the personality function!

The change here is to return a `Result` internally so we can bubble up the fatal
error, eventually translating to the appropriate error code for the libunwind
ABI.

Should help fix an accidental regression from rust-lang#39386.

Make rustdoc.js use license comments.

This will ensure that JS minifiers and the like will preserve the license statement even after minimisation.

Vec<T> is pronounced 'vec'

I've never heard it pronounced "vector". Is this an outdated recommendation?

(or have I been doing it wrong all this time)

r? @steveklabnik

…=vadimcn

std: Avoid panics in rust_eh_personality

This commit removes a few calls to panic and/or assert in `rust_eh_personality`.
This function definitely can't itself panic (that'd probably segfault or do
something else weird) and I was also noticing that a `pub extern fn foo() {}`
cdylib was abnormally large. Turns out all that size was the panicking machinery
brought in by the personality function!

The change here is to return a `Result` internally so we can bubble up the fatal
error, eventually translating to the appropriate error code for the libunwind
ABI.

…hton

bootstrap: improve 'build --help' by explaining what exactly the last example does

I recently found myself confused about what exactly gets built how often when I run which command; I think this would have helped me.

One thing I did not touch, but I feel could also be improved, is the wording just above: "For a quick build with a usable compile, you can pass".  I am not a native speaker, but this sounds odd to me. Do you mean "For a quick build of a usable compiler" (but then it should say where the usable compiler is produced)? Or do you mean "For a quick build testing if the compiler is usable"? I can reword this, but I'd like to make sure I understand the intent of the message.

What about
```
    For a quick build of a usable compiler, you can pass:

        ./x.py build --stage 1 src/libtest

    This will first build everything once (like --stage 0 without further
    arguments would), and then use the compiler built in stage 0 to build
    src/libtest and its dependencies.
    Once this is done, build/$ARCH/stage1 contains a usable compiler.
```
However, I am not sure this is actually true. In particular, why even bother building the libstd in stage 1? AFAIK that ends up in `build/*/stage1-std`, not in `build/*/stage1` (which is filled from `build/*/stage0-*`).

std: Handle ENOSYS when calling `pipe2`

Should help fix an accidental regression from rust-lang#39386.

…=nagisa

Ignore variadic FFI test on AArch64

I've cross compiled Rust to `aarch64-linux-gnu`, and tried to run the compile-fail tests, but `variadic-ffi.rs` fails with the following error:

```
The ABI `"stdcall"` is not supported for the current target [E0570]
```

The test seems to be ignored on (32-bit) ARM, so I turned it off for AArch64 too.