Switch repository layout to use a virtual manifest

The current setup has the `Cargo.toml` for `compiler-builtins` at the
repository root, which means all support crates and other files are
located within the package root. This works for now but is not the
cleanest setup since files that should or shouldn't be included in the
package need to be configured in `Cargo.toml`. If we eventually merge
`libm` development into this repository, it would be nice to make this
separation more straightforward.

Begin cleaning things up by moving the crate source to a new
`compiler-builtins` directory and adding a virtual manifest. For now the
`libm` submodule is also moved, but in the future it can likely move
back to the top level (ideally `compiler-builtins/src` would contain a
symlink to `libm/src/math`, but unfortunately it seems like Cargo does
not like something about the submodule + symlink combination).

Author: tgross35

compiler-builtins/.github/workflows/main.yml

@@ -4,7 +4,6 @@ on: [push, pull_request]
 env:
   RUSTDOCFLAGS: -Dwarnings
   RUSTFLAGS: -Dwarnings
-  RUST_COMPILER_RT_ROOT: ./compiler-rt
 
 jobs:
   test:
@@ -133,6 +132,8 @@ jobs:
       if: steps.cache-compiler-rt.outputs.cache-hit != 'true'
       run: ./ci/download-compiler-rt.sh
       shell: bash
+    - run: echo "RUST_COMPILER_RT_ROOT=$(realpath ./compiler-rt)" >> "$GITHUB_ENV"
+      shell: bash
 
     # Non-linux tests just use our raw script
     - run: ./ci/run.sh ${{ matrix.target }}

compiler-builtins/.github/workflows/publish.yml

@@ -22,7 +22,7 @@ jobs:
       - name: Install Rust (rustup)
         run: rustup update nightly --no-self-update && rustup default nightly
       - name: Publish `libm` as part of builtins, rather than its own crate
-        run: rm libm/Cargo.toml
+        run: rm compiler-builtins/libm/Cargo.toml
       - name: Run release-plz
         uses: MarcoIeni/[email protected]
         env:

compiler-builtins/.gitmodules

@@ -1,3 +1,3 @@
-[submodule "libm"]
-	path = libm
+[submodule "compiler-builtins/libm"]
+	path = compiler-builtins/libm
 	url = https://github.com/rust-lang/libm.git

compiler-builtins/Cargo.toml

@@ -1,88 +1,16 @@
-[package]
-authors = ["Jorge Aparicio <[email protected]>"]
-name = "compiler_builtins"
-version = "0.1.151"
-license = "MIT AND Apache-2.0 WITH LLVM-exception AND (MIT OR Apache-2.0)"
-readme = "README.md"
-repository = "https://github.com/rust-lang/compiler-builtins"
-homepage = "https://github.com/rust-lang/compiler-builtins"
-documentation = "https://docs.rs/compiler_builtins"
-edition = "2021"
-description = """
-Compiler intrinsics used by the Rust compiler. Also available for other targets
-if necessary!
-"""
-include = [
-  '/Cargo.toml',
-  '/build.rs',
-  '/configure.rs',
-  '/src/*',
-  '/examples/*',
-  '/LICENSE.txt',
-  '/README.md',
-  '/compiler-rt/*',
-  '/libm/src/math/*',
-]
-links = 'compiler-rt'
-
-[lib]
-test = false
-
-[dependencies]
-# For more information on this dependency see
-# https://github.com/rust-lang/rust/tree/master/library/rustc-std-workspace-core
-core = { version = "1.0.0", optional = true, package = 'rustc-std-workspace-core' }
-
-[build-dependencies]
-cc = { optional = true, version = "1.0" }
-
-[dev-dependencies]
-panic-handler = { path = 'crates/panic-handler' }
-
-[features]
-default = ["compiler-builtins"]
-
-# Enable compilation of C code in compiler-rt, filling in some more optimized
-# implementations and also filling in unimplemented intrinsics
-c = ["cc"]
-
-# Workaround for the Cranelift codegen backend. Disables any implementations
-# which use inline assembly and fall back to pure Rust versions (if avalible).
-no-asm = []
-
-# Workaround for codegen backends which haven't yet implemented `f16` and
-# `f128` support. Disabled any intrinsics which use those types.
-no-f16-f128 = []
-
-# Flag this library as the unstable compiler-builtins lib
-compiler-builtins = []
-
-# Generate memory-related intrinsics like memcpy
-mem = []
-
-# Mangle all names so this can be linked in with other versions or other
-# compiler-rt implementations. Also used for testing
-mangled-names = []
-
-# Only used in the compiler's build system
-rustc-dep-of-std = ['compiler-builtins', 'core']
-
-# This makes certain traits and function specializations public that
-# are not normally public but are required by the `testcrate`
-public-test-deps = []
-
 [workspace]
-resolver = "2"
+resolver = "3"
 members = [
-    # Note that builtins-test-intrinsics cannot be  a default member because it
+    # Note that builtins-test-intrinsics cannot be a default member because it
     # needs the `mangled-names` feature disabled, while `testcrate` needs it
     # enabled.
     "builtins-test-intrinsics",
+    "compiler-builtins",
     "testcrate",
 ]
 
 default-members = [
-    ".",
+    "compiler-builtins",
     "testcrate",
 ]
 

compiler-builtins/builtins-test-intrinsics/Cargo.toml

@@ -5,7 +5,7 @@ edition = "2021"
 publish = false
 
 [dependencies]
-compiler_builtins = { path = "../", features = ["compiler-builtins"]}
+compiler_builtins = { path = "../compiler-builtins", features = ["compiler-builtins"]}
 panic-handler = { path = '../crates/panic-handler' }
 
 [features]

compiler-builtins/builtins-test-intrinsics/build.rs

@@ -1,5 +1,5 @@
 mod builtins_configure {
-    include!("../configure.rs");
+    include!("../compiler-builtins/configure.rs");
 }
 
 fn main() {

compiler-builtins/ci/run-docker.sh

@@ -38,7 +38,7 @@ run() {
     fi
 
     if [ -d compiler-rt ]; then
-      export RUST_COMPILER_RT_ROOT=./compiler-rt
+      export RUST_COMPILER_RT_ROOT="/checkout/compiler-rt"
     fi
 
     if [ "${GITHUB_ACTIONS:-}" = "true" ]; then

compiler-builtins/ci/run.sh

@@ -23,7 +23,7 @@ fi
 if [ "${NO_STD:-}" = "1" ]; then
     echo "nothing to do for no_std"
 else
-    run="cargo test --manifest-path testcrate/Cargo.toml --no-fail-fast --target $target"
+    run="cargo test --package testcrate --no-fail-fast --target $target"
     $run
     $run --release
     $run --features c
@@ -38,7 +38,7 @@ fi
 
 if [ "${TEST_VERBATIM:-}" = "1" ]; then
     verb_path=$(cmd.exe //C echo \\\\?\\%cd%\\testcrate\\target2)
-    cargo build --manifest-path testcrate/Cargo.toml \
+    cargo build --package testcrate \
         --target "$target" --target-dir "$verb_path" --features c
 fi
 

compiler-builtins/compiler-builtins/Cargo.toml

@@ -0,0 +1,72 @@
+[package]
+authors = ["Jorge Aparicio <[email protected]>"]
+name = "compiler_builtins"
+version = "0.1.151"
+license = "MIT AND Apache-2.0 WITH LLVM-exception AND (MIT OR Apache-2.0)"
+readme = "../README.md"
+repository = "https://github.com/rust-lang/compiler-builtins"
+homepage = "https://github.com/rust-lang/compiler-builtins"
+documentation = "https://docs.rs/compiler_builtins"
+edition = "2021"
+description = """
+Compiler intrinsics used by the Rust compiler. Also available for other targets
+if necessary!
+"""
+include = [
+  '/Cargo.toml',
+  '/build.rs',
+  '/configure.rs',
+  '/src/*',
+  '../LICENSE.txt',
+  '../README.md',
+  '../compiler-rt/*',
+  'libm/src/math/*',
+]
+links = 'compiler-rt'
+
+[lib]
+test = false
+bench = false
+
+[dependencies]
+# For more information on this dependency see
+# https://github.com/rust-lang/rust/tree/master/library/rustc-std-workspace-core
+core = { version = "1.0.0", optional = true, package = 'rustc-std-workspace-core' }
+
+[build-dependencies]
+cc = { optional = true, version = "1.0" }
+
+[dev-dependencies]
+panic-handler = { path = '../crates/panic-handler' }
+
+[features]
+default = ["compiler-builtins"]
+
+# Enable compilation of C code in compiler-rt, filling in some more optimized
+# implementations and also filling in unimplemented intrinsics
+c = ["cc"]
+
+# Workaround for the Cranelift codegen backend. Disables any implementations
+# which use inline assembly and fall back to pure Rust versions (if avalible).
+no-asm = []
+
+# Workaround for codegen backends which haven't yet implemented `f16` and
+# `f128` support. Disabled any intrinsics which use those types.
+no-f16-f128 = []
+
+# Flag this library as the unstable compiler-builtins lib
+compiler-builtins = []
+
+# Generate memory-related intrinsics like memcpy
+mem = []
+
+# Mangle all names so this can be linked in with other versions or other
+# compiler-rt implementations. Also used for testing
+mangled-names = []
+
+# Only used in the compiler's build system
+rustc-dep-of-std = ['compiler-builtins', 'core']
+
+# This makes certain traits and function specializations public that
+# are not normally public but are required by the `testcrate`
+public-test-deps = []

compiler-builtins/build.rs renamed to compiler-builtins/compiler-builtins/build.rs

@@ -1,7 +1,7 @@
-use std::{collections::BTreeMap, env, path::PathBuf, sync::atomic::Ordering};
-
 mod configure;
 
+use std::{collections::BTreeMap, env, path::PathBuf, sync::atomic::Ordering};
+
 use configure::{configure_aliases, configure_f16_f128, Target};
 
 fn main() {

compiler-builtins/configure.rs renamed to compiler-builtins/compiler-builtins/configure.rs

@@ -44,8 +44,7 @@ pub mod int;
 pub mod math;
 pub mod mem;
 
-// `libm` expects its `support` module to be available in the crate root. This config can be
-// cleaned up once `libm` is made always available.
+// `libm` expects its `support` module to be available in the crate root.
 use math::libm::support;
 
 #[cfg(target_arch = "arm")]

compiler-builtins/libm renamed to compiler-builtins/compiler-builtins/libm

@@ -5,4 +5,8 @@ authors = ["Alex Crichton <[email protected]>"]
 edition = "2024"
 publish = false
 
+[lib]
+test = false
+bench = false
+
 [dependencies]

compiler-builtins/src/aarch64.rs renamed to compiler-builtins/compiler-builtins/src/aarch64.rs

@@ -18,7 +18,7 @@ rand_xoshiro = "0.6"
 rustc_apfloat = "0.2.1"
 
 [dependencies.compiler_builtins]
-path = ".."
+path = "../compiler-builtins"
 default-features = false
 features = ["public-test-deps"]
 

compiler-builtins/src/aarch64_linux.rs renamed to compiler-builtins/compiler-builtins/src/aarch64_linux.rs

@@ -1,7 +1,7 @@
 use std::collections::HashSet;
 
 mod builtins_configure {
-    include!("../configure.rs");
+    include!("../compiler-builtins/configure.rs");
 }
 
 /// Features to enable