I've wanted something like this myself. I dislike using `--open`
because I tend to move up to re-run my `cargo doc` run but then have to
edit it to remove `--open`.
Also makes it annoying when opening docs when `cargo doc` is wrapped by
a tool like `make`.
This was previously attempted in #5592:
- Unlike the request in #5562, this aligns with #5592 in always printing
rather than using a flag as this seems generally useful
- Unlike #5592, this prints as an alternative to "Opening" to keep
things light
- Unlike #5592, this prints afterwards as the link is only valid then
Fixes#5562
It was unnecessary to pass `spilt-debuginfo` if there is no debuginfo.
Tests are touched here only for matching rustflags invocation stderr
in the original test suite.
Previously, `Debuginfo::None` meant "don't pass -C debuginfo" and `Explicit(None)` meant
"-C debuginfo=0", which occasionally led to caching bugs where cargo would sometimes pass
`-C debuginfo=0` and sometimes not. There are no such bugs currently that we know of, but
representing them the same within cargo avoids the possibility of the bug popping up again in the
future.
I tested the `with_stderr_does_not_contain_tests` with this diff to ensure they did not pass:
```diff
diff --git a/src/cargo/core/compiler/mod.rs b/src/cargo/core/compiler/mod.rs
index 55ec17182..c186dd00a 100644
--- a/src/cargo/core/compiler/mod.rs
+++ b/src/cargo/core/compiler/mod.rs
@@ -1073,9 +1073,7 @@ fn build_base_args(
let debuginfo = debuginfo.into_inner();
// Shorten the number of arguments if possible.
- if debuginfo != TomlDebugInfo::None {
cmd.arg("-C").arg(format!("debuginfo={}", debuginfo));
- }
cmd.args(unit.pkg.manifest().lint_rustflags());
if !rustflags.is_empty() {
```
The weakening of debuginfo for build script shouldn't turn debuginfo
to `DebugInfo::None`. That will result in not passing `-C debuginfo=0`
to rustc, leading to build artifact cache miss.
Add some assertions to ensure that debuginfo is not used to compile
build dependencies, in a way that differs between the old and new
defaults: some of the assert elision could match the previous defaults
with debuginfo. These new assertions break if `-C debuginfo` is present
in the commands cargo ran.
This commit updates Cargo's build of host dependencies to build them
with optimization level 0 by default instead of matching the profile of
the final binary.
Since Cargo's inception build dependencies have, by default, been built
in a profile that largely matches the profile of the final target
artifact. Build dependencies, however, rarely actually need to be
optimized and are often executing very small tasks, which means that
optimizing them often wastes a lot of build time. A great example of
this is procedural macros where `syn` and friends are pretty heavyweight
to optimize, and the amount of Rust code they're parsing is typically
quite small, so the time spent optimizing rarely comes as a benefit.
The goal of this PR is to improve build times on average in the
community by not spending time optimizing build dependencies (build
scripts, procedural macros, and their transitive dependencies). The PR
will not be a universal win for everyone, however. There's some
situations where your build time may actually increase:
* In some cases build scripts and procedural macros can take quite a
long time to run!
* Cargo may not build dependencies more than once if they're shared with
the main build. This only applies to builds without `--target` where
the same crate is used in the final binary as in a build script.
In these cases, however, the `build-override` profile has existed for
some time know and allows giving a knob to tweak this behavior. For
example to get back the previous build behavior of Cargo you would
specify, in `Cargo.toml`:
[profile.release.build-override]
opt-level = 3
or you can configure this via the environment:
export CARGO_PROFILE_RELEASE_BUILD_OVERRIDE_OPT_LEVEL=3
There are two notable features we would like to add in the future which
would make the impact of a change like this smaller, but they're not
implemented at this time (nor do we have concrete plans to implement
them). First we would like crates to have a way of specifying they
should be optimized by default, despite default profile options. Often
crates, like lalrpop historically, have abysmal performance in debug
mode and almost always (even in debug builds) want to be built in
release mode. The second feature is that ideally crate authors would be
able to tell Cargo to minimize the number of crates built, unifying
profiles where possible to avoid double-compiling crates.
At this time though the Cargo team feels that the benefit of changing
the defaults is well worth this change. Neither today nor directly after
this change will be a perfect world, but it's hoped that this change
makes things less bad!
This commit is the Cargo half of support necessary for
rust-lang/rust#70458. Today the compiler emits embedded bytecode in
rlibs by default, but compresses it. This is both extraneous disk space
and wasted build time for almost all builds, so the PR in question there
is changing rustc to have a `-Cembed-bitcode` flag which, when enabled,
places the bitcode in the object file rather than an auxiliary file (no
extra compression), but also enables `-Cembed-bitcode=no` to disable
bitcode emission entirely.
This Cargo support changes Cargo to pass `-Cembed-bitcode=no` for almost
all compilations. Cargo will keep `lto = true` and such working by not
passing this flag (and thus allowing bitcode to get embedded), but by
default `cargo build` and `cargo build --release` will no longer have
any bitcode in rlibs which should result in speedier builds!
Most of the changes here were around the test suite and various
assertions about the `rustc` command lines we spit out. One test was
hard-disabled until we can get `-Cembed-bitcode=no` into nightly, and
then we can make it a nightly-only test. The test will then be stable
again once `-Cembed-bitcode=no` hits stable.
Note that this is intended to land before the upstream `-Cembed-bitcode`
change. The thinking is that we'll land everything in rust-lang/rust all
at once so there's no build time regressions for anyone. If we were to
land the `-Cembed-bitcode` PR first then there would be a build time
regression until we land Cargo changes because rustc would be emitting
uncompressed bitcode by default and Cargo wouldn't be turning it off.
The effects over the profile used by targets are made conditional
in this commit, using the old scheme if the `named-profiles` feature
is disabled. This also affects the `profile_targets` tests, which
now have two modes - stable, and nightly with the feature enabled.
This commit starts to lay the groundwork for #6660 where Cargo will
invoke rustc in a "pipelined" fashion. The goal here is to execute one
command to produce both an `*.rmeta` file as well as an `*.rlib` file
for candidate compilations. In that case if another rlib depends on that
compilation, then it can start as soon as the `*.rmeta` is ready and not
have to wait for the `*.rlib` compilation.
Initially attempted in #6864 with a pretty invasive refactoring this
iteration is much more lightweight and fits much more cleanly into
Cargo's backend. The approach taken here is to update the
`DependencyQueue` structure to carry a piece of data on each dependency
edge. This edge information represents the artifact that one node
requires from another, and then we a node has no outgoing edges it's
ready to build.
A dependency on a metadata file is modeled as just that, a dependency on
just the metadata and not the full build itself. Most of cargo's backend
doesn't really need to know about this edge information so it's
basically just calculated as we insert nodes into the `DependencyQueue`.
Once that's all in place it's just a few pieces here and there to
identify compilations that *can* be pipelined and then they're wired up
to depend on the rmeta file instead of the rlib file.
This picks up on the work done in PR #5683.
The extra output is only displayed with `-vv`.
The Windows output has the form `set FOO=foo && BAR=bar rustc ...` instead of
the form that suggested in #5683 to make escaping easier and since it's
simpler.
cargo's extra verbose mode is useful for getting detailed information out of
builds in CI where it can be difficult to examine the build environment
after-the-fact. However, when multiple build scripts are running as part of a
build it's not always clear what output is from which build script. This patch
makes cargo prefix each line of build script output with the crate name and
version this case.
* Collapse the nested cargotest::support module into the cargotest
module (merge the mod.rs's)
* Rename the cargotest module to support
* Nest the top-level hamcrest module into support
By rewriting the tests, with rerast (https://github.com/google/rerast),
to use the newly introduced "at" method.
First I added the following temporary function to cargotest::support:
pub fn project_foo() -> ProjectBuilder {
project("foo")
}
Then I defined the following rewrite.rs:
use cargotest::support::{ project, project_foo };
fn rule1(a: &'static str) {
replace!(project("foo") => project_foo());
replace!(project(a) => project_foo().at(a));
}
Then I ran rerast:
cargo +nightly rerast --rules_file=rewrite.rs --force --targets tests --file tests/testsuite/main.rs
Finally I searched and replaced the references to project_foo with
argument-less project (a little awkardly on macOS with a git clean).
find tests -type f -exec sed -i -e 's/project_foo/project/g' {} +
git clean -d tests
