Merge branch 'master' into miri-memory

.github/workflows/ci.yml

@@ -32,7 +32,7 @@ jobs:
     env:
       HOST_TARGET: ${{ matrix.host_target }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Show Rust version (stable toolchain)
         run: |
@@ -45,7 +45,7 @@ jobs:
       # over time).
       - name: Add cache for cargo
         id: cache
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: |
             # Taken from <https://doc.rust-lang.org/nightly/cargo/guide/cargo-home.html#caching-the-cargo-home-in-ci>.
@@ -57,12 +57,12 @@ jobs:
             ~/.cargo/bin
             ~/.cargo/.crates.toml
             ~/.cargo/.crates2.json
-          key: cargo-${{ runner.os }}-reset20240331-${{ hashFiles('**/Cargo.lock') }}
-          restore-keys: cargo-${{ runner.os }}-reset20240331
+          key: cargo-${{ runner.os }}-reset20240425-${{ hashFiles('**/Cargo.lock') }}
+          restore-keys: cargo-${{ runner.os }}-reset20240425
 
-      - name: Install rustup-toolchain-install-master
-        if: ${{ steps.cache.outputs.cache-hit != 'true' }}
-        run: cargo install -f rustup-toolchain-install-master
+      - name: Install tools
+        if: steps.cache.outputs.cache-hit != 'true'
+        run: cargo install -f rustup-toolchain-install-master hyperfine
 
       - name: Install miri toolchain
         run: |
@@ -78,14 +78,20 @@ jobs:
           rustc -Vv
           cargo -V
 
+      # The `style` job only runs on Linux; this makes sure the Windows-host-specific
+      # code is also covered by clippy.
+      - name: Check clippy
+        if: matrix.os == 'windows-latest'
+        run: ./miri clippy -- -D warnings
+
       - name: Test Miri
         run: ./ci/ci.sh
 
   style:
     name: style checks
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       # This is exactly duplicated from above. GHA is pretty terrible when it comes
       # to avoiding code duplication.
@@ -95,7 +101,7 @@ jobs:
       # over time).
       - name: Add cache for cargo
         id: cache
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: |
             # Taken from <https://doc.rust-lang.org/nightly/cargo/guide/cargo-home.html#caching-the-cargo-home-in-ci>.
@@ -111,7 +117,7 @@ jobs:
           restore-keys: cargo-${{ runner.os }}-reset20240331
 
       - name: Install rustup-toolchain-install-master
-        if: ${{ steps.cache.outputs.cache-hit != 'true' }}
+        if: steps.cache.outputs.cache-hit != 'true'
         run: cargo install -f rustup-toolchain-install-master
 
       - name: Install "master" toolchain
@@ -165,7 +171,7 @@ jobs:
     name: cronjob failure notification
     runs-on: ubuntu-latest
     needs: [build, style]
-    if: github.event_name == 'schedule' && (failure() || cancelled())
+    if: github.event_name == 'schedule' && failure()
     steps:
       # Send a Zulip notification
       - name: Install zulip-send
@@ -191,7 +197,7 @@ jobs:
           The Miri Cronjobs Bot'
 
       # Attempt to auto-sync with rustc
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 256 # get a bit more of the history
       - name: install josh-proxy

.gitignore

@@ -9,5 +9,5 @@ tex/*/out
 perf.data
 perf.data.old
 flamegraph.svg
-tests/extern-so/libtestlib.so
+tests/native-lib/libtestlib.so
 .auto-*

CONTRIBUTING.md

@@ -72,14 +72,14 @@ For example:
 
 You can (cross-)run the entire test suite using:
 
-```
+```sh
 ./miri test
-MIRI_TEST_TARGET=i686-unknown-linux-gnu ./miri test
+./miri test --target i686-unknown-linux-gnu
 ```
 
 `./miri test FILTER` only runs those tests that contain `FILTER` in their filename (including the
-base directory, e.g. `./miri test fail` will run all compile-fail tests). These filters are passed
-to `cargo test`, so for multiple filters you need to use `./miri test -- FILTER1 FILTER2`.
+base directory, e.g. `./miri test fail` will run all compile-fail tests). Multiple filters are
+supported: `./miri test FILTER1 FILTER2` runs all tests that contain either string.
 
 #### Fine grained logging
 
@@ -139,9 +139,8 @@ and then you can use it as if it was installed by `rustup` as a component of the
 in the `miri` toolchain's sysroot to prevent conflicts with other toolchains.
 The Miri binaries in the `cargo` bin directory (usually `~/.cargo/bin`) are managed by rustup.
 
-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.
+There's a test for the cargo wrapper in the `test-cargo-miri` directory; run `./run-test.py` in
+there to execute it. You can pass `--target` to execute the test for another target.
 
 ### Using a modified standard library
 
@@ -287,3 +286,41 @@ https. Add the following to your `.gitconfig`:
 [url "git@github.com:"]
     pushInsteadOf = https://github.com/
 ```
+
+## Internal environment variables
+
+The following environment variables are *internal* and must not be used by
+anyone but Miri itself. They are used to communicate between different Miri
+binaries, and as such worth documenting:
+
+* `CARGO_EXTRA_FLAGS` is understood by `./miri` and passed to all host cargo invocations.
+* `MIRI_BE_RUSTC` can be set to `host` or `target`. It tells the Miri driver to
+  actually not interpret the code but compile it like rustc would. With `target`, Miri sets
+  some compiler flags to prepare the code for interpretation; with `host`, this is not done.
+  This environment variable is useful to be sure that the compiled `rlib`s are compatible
+  with Miri.
+* `MIRI_CALLED_FROM_SETUP` is set during the Miri sysroot build,
+  which will re-invoke `cargo-miri` as the `rustc` to use for this build.
+* `MIRI_CALLED_FROM_RUSTDOC` when set to any value tells `cargo-miri` that it is
+  running as a child process of `rustdoc`, which invokes it twice for each doc-test
+  and requires special treatment, most notably a check-only build before interpretation.
+  This is set by `cargo-miri` itself when running as a `rustdoc`-wrapper.
+* `MIRI_CWD` when set to any value tells the Miri driver to change to the given
+  directory after loading all the source files, but before commencing
+  interpretation. This is useful if the interpreted program wants a different
+  working directory at run-time than at build-time.
+* `MIRI_LOCAL_CRATES` is set by `cargo-miri` to tell the Miri driver which
+  crates should be given special treatment in diagnostics, in addition to the
+  crate currently being compiled.
+* `MIRI_ORIG_RUSTDOC` is set and read by different phases of `cargo-miri` to remember the
+  value of `RUSTDOC` from before it was overwritten.
+* `MIRI_REPLACE_LIBRS_IF_NOT_TEST` when set to any value enables a hack that helps bootstrap
+  run the standard library tests in Miri.
+* `MIRI_TEST_TARGET` is set by `./miri test` (and `./x.py test miri`) to tell the test harness about
+  the chosen target.
+* `MIRI_VERBOSE` when set to any value tells the various `cargo-miri` phases to
+  perform verbose logging.
+* `MIRI_HOST_SYSROOT` is set by bootstrap to tell `cargo-miri` which sysroot to use for *host*
+  operations.
+* `RUSTC_BLESS` is set by `./miri test` (and `./x.py test miri`) to indicate bless-mode to the test
+  harness.