mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Auto merge of #1949 - RalfJung:miri-lib-src, r=oli-obk

Browse Source 
add and document MIRI_LIB_SRC env var to set the source from which Miri builds the standard library

This is just an alias of `XARGO_RUST_SRC`, but avoids exposing how exactly we use xargo.
This commit is contained in:
bors 2021-12-23 15:54:25 +00:00
commit 2170d7a7c9
3 changed files with 29 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
CONTRIBUTING.md
View File

@ -107,6 +107,16 @@ There's a test for the cargo wrapper in the `test-cargo-miri` directory; run
`./run-test.py` in there to execute it. Like `./miri test`, this respects the
`MIRI_TEST_TARGET` environment variable to execute the test for another target.
### Using a modified standard library
Miri re-builds the standard library into a custom sysroot, so it is fairly easy
to test Miri against a modified standard library -- you do not even have to
build Miri yourself, the Miri shipped by `rustup` will work. All you have to do
is set the `MIRI_LIB_SRC` environment variable to the `library` folder of a
`rust-lang/rust` repository checkout. Note that changing files in that directory
does not automatically trigger a re-build of the standard library; you have to
clear the Miri build cache manually (on Linux, `rm -rf ~/.cache/miri`).
## Configuring `rust-analyzer`
To configure `rust-analyzer` and VS Code for working on Miri, save the following

6
README.md
View File

@ -306,6 +306,12 @@ Moreover, Miri recognizes some environment variables:
Miri executions, also [see "Testing the Miri driver" in `CONTRIBUTING.md`][testing-miri].
* `MIRIFLAGS` (recognized by `cargo miri` and the test suite) defines extra
flags to be passed to Miri.
* `MIRI_LIB_SRC` defines the directory where Miri expects the sources of the
standard library that it will build and use for interpretation. This directory
must point to the `library` subdirectory of a `rust-lang/rust` repository
checkout. Note that changing files in that directory does not automatically
trigger a re-build of the standard library; you have to clear the Miri build
cache manually (on Linux, `rm -rf ~/.cache/miri`).
* `MIRI_SYSROOT` (recognized by `cargo miri` and the test suite)
indicates the sysroot to use. To do the same thing with `miri`
directly, use the `--sysroot` flag.

16
cargo-miri/bin.rs
View File

@ -1,5 +1,5 @@
use std::env;
use std::ffi::OsString;
use std::ffi::{OsStr, OsString};
use std::fmt::Write as _;
use std::fs::{self, File};
use std::io::{self, BufRead, BufReader, BufWriter, Read, Write};
@ -341,8 +341,11 @@ fn setup(subcommand: MiriCommand) {
ask_to_run(cmd, ask_user, "install a recent enough xargo");
}
// Determine where the rust sources are located. `XARGO_RUST_SRC` env var trumps everything.
let rust_src = match std::env::var_os("XARGO_RUST_SRC") {
// Determine where the rust sources are located. The env vars manually setting the source
// (`MIRI_LIB_SRC`, `XARGO_RUST_SRC`) trump auto-detection.
let rust_src_env_var =
std::env::var_os("MIRI_LIB_SRC").or_else(|| std::env::var_os("XARGO_RUST_SRC"));
let rust_src = match rust_src_env_var {
Some(path) => {
let path = PathBuf::from(path);
// Make path absolute if possible.
@ -376,6 +379,13 @@ fn setup(subcommand: MiriCommand) {
if !rust_src.exists() {
show_error(format!("given Rust source directory `{}` does not exist.", rust_src.display()));
}
if rust_src.file_name().and_then(OsStr::to_str) != Some("library") {
show_error(format!(
"given Rust source directory `{}` does not seem to be the `library` subdirectory of \
a Rust source checkout.",
rust_src.display()
));
}
// Next, we need our own libstd. Prepare a xargo project for that purpose.
// We will do this work in whatever is a good cache dir for this platform.