From c9c8fb88cf1be7e0a6bd6fd049d8d28fb5d86135 Mon Sep 17 00:00:00 2001
From: Joshua Nelson <jyn514@gmail.com>
Date: Sat, 12 Sep 2020 00:42:52 -0400
Subject: [PATCH] Add sample defaults for config.toml
- Allow including defaults in `src/bootstrap/defaults` using `profile = "..."`
- Add default config files
- Combine config files using the merge dependency.
- Add comments to default config files
- Add a README asking to open an issue if the defaults are bad
- Give a loud error if trying to merge `.target`, since it's not
currently supported
- Use an exhaustive match
- Use `<none>` in config.toml.example to avoid confusion
- Fix bugs in `Merge` derives
Previously, it would completely ignore the profile defaults if there
were any settings in `config.toml`. I sent an email to the `merge` maintainer
asking them to make the behavior in this commit the default.
This introduces a new dependency on `merge` that hasn't yet been vetted.
I want to improve the output when `include = "x"` isn't found:
```
thread 'main' panicked at 'fs::read_to_string(&file) failed with No such file or directory (os error 2) ("configuration file did not exist")', src/bootstrap/config.rs:522:28
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
failed to run: /home/joshua/rustc/build/bootstrap/debug/bootstrap test tidy
Build completed unsuccessfully in 0:00:00
```
However that seems like it could be fixed in a follow-up.
---
Cargo.lock | 23 +++++++
config.toml.example | 10 +++
src/bootstrap/Cargo.toml | 1 +
src/bootstrap/config.rs | 74 ++++++++++++++-------
src/bootstrap/defaults/README.md | 11 +++
src/bootstrap/defaults/config.toml.codegen | 13 ++++
src/bootstrap/defaults/config.toml.compiler | 8 +++
src/bootstrap/defaults/config.toml.library | 10 +++
src/bootstrap/defaults/config.toml.user | 9 +++
9 files changed, 135 insertions(+), 24 deletions(-)
create mode 100644 src/bootstrap/defaults/README.md
create mode 100644 src/bootstrap/defaults/config.toml.codegen
create mode 100644 src/bootstrap/defaults/config.toml.compiler
create mode 100644 src/bootstrap/defaults/config.toml.library
create mode 100644 src/bootstrap/defaults/config.toml.user
diff --git a/Cargo.lock b/Cargo.lock
index d3f777bc663..4c55fea30e0 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -207,6 +207,7 @@ dependencies = [
"ignore",
"lazy_static",
"libc",
+ "merge",
"num_cpus",
"opener",
"pretty_assertions",
@@ -1900,6 +1901,28 @@ dependencies = [
"autocfg",
]
+[[package]]
+name = "merge"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "10bbef93abb1da61525bbc45eeaff6473a41907d19f8f9aa5168d214e10693e9"
+dependencies = [
+ "merge_derive",
+ "num-traits",
+]
+
+[[package]]
+name = "merge_derive"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "209d075476da2e63b4b29e72a2ef627b840589588e71400a25e3565c4f849d07"
+dependencies = [
+ "proc-macro-error",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
[[package]]
name = "minifier"
version = "0.0.33"
diff --git a/config.toml.example b/config.toml.example
index 99e6f9dceb4..8bf1b48ce83 100644
--- a/config.toml.example
+++ b/config.toml.example
@@ -9,6 +9,16 @@
# a custom configuration file can also be specified with `--config` to the build
# system.
+# =============================================================================
+# Global Settings
+# =============================================================================
+
+# Use different pre-set defaults than the global defaults.
+#
+# See `src/bootstrap/defaults` for more information.
+# Note that this has no default value (x.py uses the defaults in `config.toml.example`).
+#profile = <none>
+
# =============================================================================
# Tweaking how LLVM is compiled
# =============================================================================
diff --git a/src/bootstrap/Cargo.toml b/src/bootstrap/Cargo.toml
index faec2c53742..0177a9dab97 100644
--- a/src/bootstrap/Cargo.toml
+++ b/src/bootstrap/Cargo.toml
@@ -48,6 +48,7 @@ lazy_static = "1.3.0"
time = "0.1"
ignore = "0.4.10"
opener = "0.4"
+merge = "0.1.0"
[target.'cfg(windows)'.dependencies.winapi]
version = "0.3"
diff --git a/src/bootstrap/config.rs b/src/bootstrap/config.rs
index 7e2cb772186..d925af19a84 100644
--- a/src/bootstrap/config.rs
+++ b/src/bootstrap/config.rs
@@ -16,6 +16,7 @@ use crate::flags::Flags;
pub use crate::flags::Subcommand;
use crate::util::exe;
use build_helper::t;
+use merge::Merge;
use serde::Deserialize;
macro_rules! check_ci_llvm {
@@ -278,10 +279,31 @@ struct TomlConfig {
rust: Option<Rust>,
target: Option<HashMap<String, TomlTarget>>,
dist: Option<Dist>,
+ profile: Option<String>,
+}
+
+impl Merge for TomlConfig {
+ fn merge(&mut self, TomlConfig { build, install, llvm, rust, dist, target, profile: _ }: Self) {
+ fn do_merge<T: Merge>(x: &mut Option<T>, y: Option<T>) {
+ if let Some(new) = y {
+ if let Some(original) = x {
+ original.merge(new);
+ } else {
+ *x = Some(new);
+ }
+ }
+ };
+ do_merge(&mut self.build, build);
+ do_merge(&mut self.install, install);
+ do_merge(&mut self.llvm, llvm);
+ do_merge(&mut self.rust, rust);
+ do_merge(&mut self.dist, dist);
+ assert!(target.is_none(), "merging target-specific config is not currently supported");
+ }
}
/// TOML representation of various global build decisions.
-#[derive(Deserialize, Default, Clone)]
+#[derive(Deserialize, Default, Clone, Merge)]
#[serde(deny_unknown_fields, rename_all = "kebab-case")]
struct Build {
build: Option<String>,
@@ -321,7 +343,7 @@ struct Build {
}
/// TOML representation of various global install decisions.
-#[derive(Deserialize, Default, Clone)]
+#[derive(Deserialize, Default, Clone, Merge)]
#[serde(deny_unknown_fields, rename_all = "kebab-case")]
struct Install {
prefix: Option<String>,
@@ -338,7 +360,7 @@ struct Install {
}
/// TOML representation of how the LLVM build is configured.
-#[derive(Deserialize, Default)]
+#[derive(Deserialize, Default, Merge)]
#[serde(deny_unknown_fields, rename_all = "kebab-case")]
struct Llvm {
skip_rebuild: Option<bool>,
@@ -365,7 +387,7 @@ struct Llvm {
download_ci_llvm: Option<bool>,
}
-#[derive(Deserialize, Default, Clone)]
+#[derive(Deserialize, Default, Clone, Merge)]
#[serde(deny_unknown_fields, rename_all = "kebab-case")]
struct Dist {
sign_folder: Option<String>,
@@ -389,7 +411,7 @@ impl Default for StringOrBool {
}
/// TOML representation of how the Rust build is configured.
-#[derive(Deserialize, Default)]
+#[derive(Deserialize, Default, Merge)]
#[serde(deny_unknown_fields, rename_all = "kebab-case")]
struct Rust {
optimize: Option<bool>,
@@ -434,7 +456,7 @@ struct Rust {
}
/// TOML representation of how each build target is configured.
-#[derive(Deserialize, Default)]
+#[derive(Deserialize, Default, Merge)]
#[serde(deny_unknown_fields, rename_all = "kebab-case")]
struct TomlTarget {
cc: Option<String>,
@@ -523,27 +545,31 @@ impl Config {
}
#[cfg(test)]
- let toml = TomlConfig::default();
+ let get_toml = |_| TomlConfig::default();
#[cfg(not(test))]
- let toml = flags
- .config
- .map(|file| {
- use std::process;
+ let get_toml = |file: PathBuf| {
+ use std::process;
- let contents = t!(fs::read_to_string(&file));
- match toml::from_str(&contents) {
- Ok(table) => table,
- Err(err) => {
- println!(
- "failed to parse TOML configuration '{}': {}",
- file.display(),
- err
- );
- process::exit(2);
- }
+ let contents = t!(fs::read_to_string(&file), "configuration file did not exist");
+ match toml::from_str(&contents) {
+ Ok(table) => table,
+ Err(err) => {
+ println!("failed to parse TOML configuration '{}': {}", file.display(), err);
+ process::exit(2);
}
- })
- .unwrap_or_else(TomlConfig::default);
+ }
+ };
+
+ let mut toml = flags.config.map(get_toml).unwrap_or_else(TomlConfig::default);
+ if let Some(include) = &toml.profile {
+ let mut include_path = config.src.clone();
+ include_path.push("src");
+ include_path.push("bootstrap");
+ include_path.push("defaults");
+ include_path.push(format!("config.toml.{}", include));
+ let included_toml = get_toml(include_path);
+ toml.merge(included_toml);
+ }
let build = toml.build.unwrap_or_default();
diff --git a/src/bootstrap/defaults/README.md b/src/bootstrap/defaults/README.md
new file mode 100644
index 00000000000..a91fc3538eb
--- /dev/null
+++ b/src/bootstrap/defaults/README.md
@@ -0,0 +1,11 @@
+# About bootstrap defaults
+
+These defaults are intended to be a good starting point for working with x.py,
+with the understanding that no one set of defaults make sense for everyone.
+
+They are still experimental, and we'd appreciate your help improving them!
+If you use a setting that's not in these defaults that you think others would benefit from, please [file an issue] or make a PR with the changes.
+Similarly, if one of these defaults doesn't match what you use personally,
+please open an issue to get it changed.
+
+[file an issue]: https://github.com/rust-lang/rust/issues/new/choose
diff --git a/src/bootstrap/defaults/config.toml.codegen b/src/bootstrap/defaults/config.toml.codegen
new file mode 100644
index 00000000000..a9505922ca7
--- /dev/null
+++ b/src/bootstrap/defaults/config.toml.codegen
@@ -0,0 +1,13 @@
+# These defaults are meant for contributors to the compiler who modify codegen or LLVM
+[llvm]
+# This enables debug-assertions in LLVM,
+# catching logic errors in codegen much earlier in the process.
+assertions = true
+
+[rust]
+# This enables `RUSTC_LOG=debug`, avoiding confusing situations
+# where adding `debug!()` appears to do nothing.
+# However, it makes running the compiler slightly slower.
+debug-logging = true
+# This greatly increases the speed of rebuilds, especially when there are only minor changes. However, it makes the initial build slightly slower.
+incremental = true
diff --git a/src/bootstrap/defaults/config.toml.compiler b/src/bootstrap/defaults/config.toml.compiler
new file mode 100644
index 00000000000..4772de8a2cb
--- /dev/null
+++ b/src/bootstrap/defaults/config.toml.compiler
@@ -0,0 +1,8 @@
+# These defaults are meant for contributors to the compiler who do not modify codegen or LLVM
+[rust]
+# This enables `RUSTC_LOG=debug`, avoiding confusing situations
+# where adding `debug!()` appears to do nothing.
+# However, it makes running the compiler slightly slower.
+debug-logging = true
+# This greatly increases the speed of rebuilds, especially when there are only minor changes. However, it makes the initial build slightly slower.
+incremental = true
diff --git a/src/bootstrap/defaults/config.toml.library b/src/bootstrap/defaults/config.toml.library
new file mode 100644
index 00000000000..e4316f4d864
--- /dev/null
+++ b/src/bootstrap/defaults/config.toml.library
@@ -0,0 +1,10 @@
+# These defaults are meant for contributors to the standard library and documentation.
+[build]
+# When building the standard library, you almost never want to build the compiler itself.
+build-stage = 0
+test-stage = 0
+bench-stage = 0
+
+[rust]
+# This greatly increases the speed of rebuilds, especially when there are only minor changes. However, it makes the initial build slightly slower.
+incremental = true
diff --git a/src/bootstrap/defaults/config.toml.user b/src/bootstrap/defaults/config.toml.user
new file mode 100644
index 00000000000..6647061d88f
--- /dev/null
+++ b/src/bootstrap/defaults/config.toml.user
@@ -0,0 +1,9 @@
+# These defaults are meant for users and distro maintainers building from source, without intending to make multiple changes.
+[build]
+# When compiling from source, you almost always want a full stage 2 build,
+# which has all the latest optimizations from nightly.
+build-stage = 2
+test-stage = 2
+doc-stage = 2
+# When compiling from source, you usually want all tools.
+extended = true