Infrastructure

[fitzgen]

Common infrastructure types we will need: an Error type, an Options builder`, CLI arg parsing.

r? @tschneidereit

[fitzgen]

Ah ok, CI is failing because we need to have newer GCC. Will update in a bit.

[tschneidereit]

Looks good, apart from the nit below. r=me with that and the GCC issue fixed.

[tschneidereit]

Let's start this off with proper separation and not include this in lib.rs: the library shouldn't know about arg parsing. (Yes, I realize this is all scaffolding, but this is strictly code we'd remove from this file later on anyway.)

[fitzgen]

You want to move the cli mod into src/bin/starling.rs, or you don't want the module to be pub, or you want it to be in a whole new crate? It's not clear to me what you're requesting here.

[tschneidereit]

I really didn't make that clear at all, sorry. I think the use of cli shouldn't be in src/lib.rs. src/bin/starling.rs sounds like a good place for it.

[fitzgen]

g++-5: internal compiler error: Killed (program cc1plus)

[fitzgen]

g++-6: internal compiler error: Killed (program cc1plus)

Crap.

[fitzgen]

Wait, I think the ICEs are just from the process getting killed in the middle of compilation.

I think this is the real culprit:

warning: build failed, waiting for other jobs to finish...
warning: variable does not need to be mutable
   --> /home/travis/.cargo/registry/src/github.com-1ecc6299db9ec823/syntex_syntax-0.58.1/src/ext/tt/macro_parser.rs:204:63
    |
204 |     fn n_rec<I: Iterator<Item=Rc<NamedMatch>>>(m: &TokenTree, mut res: &mut I,
    |                                                               ^^^^^^^
    |
note: lint level defined here
   --> /home/travis/.cargo/registry/src/github.com-1ecc6299db9ec823/syntex_syntax-0.58.1/src/lib.rs:23:9
    |
23  | #![deny(warnings)]
    |         ^^^^^^^^

[fitzgen]

And that is actually triggered by a cargo bug: serde-deprecated/syntex#119

[fitzgen]

Er, rust-lang/cargo#3823

[fitzgen]

Hrm, it seems we're still ICEing:

{standard input}: Assembler messages:
{standard input}:16702: Warning: end of file not at end of a line; newline inserted
{standard input}:17014: Error: unknown pseudo-op: `.p2'
{standard input}: Error: open CFI at the end of file; missing .cfi_endproc directive
g++-6: internal compiler error: Killed (program cc1plus)

[tschneidereit]

@fitzgen, is this something we should talk to cargo folks about, or just something that needs a little more digging?

[fitzgen]

@fitzgen, is this something we should talk to cargo folks about, or just something that needs a little more digging?

We were running into an issue where -vv to enable "very verbose" mode was also making warnings into errors in our dependencies, which was breaking the build. That is fixed but not released, but we can work around it by building with only -v instead of -vv.

The thing keeping this from landing right now, is that AFAICT those gcc ICEs are real, and I haven't been able to find a gcc version that doesn't ICE yet. This is a bit confusing to me, since earlier/other PRs with this same mozjs have all been A-OK with gcc.

Digging in more.

[fitzgen]

So I think the ICEs are an unrelated goose chase.

Even without -v, syntex_syntax is failing to compile:

error: Could not compile `syntex_syntax`.

And that's all the information that's getting spit out in the logs...

And yet it works just fine locally.

[fitzgen]

On IRC acrichto says that this might be cargo swallowing the error, perhaps because of OOM.

[tschneidereit]

On IRC acrichto says that this might be cargo swallowing the error, perhaps because of OOM.

Ugh. Can you try compiling with fewer threads to see if that's the case?

[fitzgen]

Trying with CARGO_BUILD_JOBS=4.

[fitzgen]

Ok, by restricting to one parallel jobs everywhere, 1/4 (so far) CI tasks finished successfully without OOMing, while 3/4 hit the travis CI time limit.

Time to slowly introduce more parallel jobs again.

[fitzgen]

4 parallel jobs = some are timing out; 8 parallel jobs = OOM

[fitzgen]

6 parallel jobs is also OOMing.

[fitzgen]

Going to just merge this, since we are planning on dealing with CI later, and other PRs build on top of this.