Rollup merge of #130068 - madsmtm:deployment-target-test, r=jieyouxu

Test codegen when setting deployment target

Test our codegen in different scenarios when setting the deployment target. There are many places here where this is still incorrect, these will be fixed in #129342, #129367 and #129369. See #129432 for the bigger picture.

Tested locally using:
```console
./x test tests/run-make/apple-deployment-target --target="aarch64-apple-darwin,aarch64-apple-ios,aarch64-apple-ios-macabi,aarch64-apple-ios-sim,aarch64-apple-tvos,aarch64-apple-tvos-sim,aarch64-apple-visionos,aarch64-apple-visionos-sim,aarch64-apple-watchos,aarch64-apple-watchos-sim,arm64_32-apple-watchos,armv7s-apple-ios,i386-apple-ios,x86_64-apple-darwin,x86_64-apple-ios,x86_64-apple-ios-macabi,x86_64-apple-tvos,x86_64-apple-watchos-sim,x86_64h-apple-darwin"
```

The only Apple targets that aren't tested by the above command are:
- `arm64e-apple-darwin`, failed to build, see rust-lang/cc-rs#1205.
- `armv7k-apple-watchos`, failed to link, see #130071.
- `arm64e-apple-ios`, failed to link, see #130085.
- `i686-apple-darwin`, requires a bit of setup and an older machine, see [the docs](https://doc.rust-lang.org/nightly/rustc/platform-support/i686-apple-darwin.html).
- `i386-apple-ios` requires you to set `IPHONEOS_DEPLOYMENT_TARGET=10.0` for the test helpers to work, will be fixed by rust-lang/cc-rs#1030.

But all of this is as it was before this PR.

Fixes #47825, since we now have a test that compiles a `dylib` for `aarch64-apple-ios`.

Split out from #129342, see that for a little bit of the review that this has gone through already.

r? petrochenkov

```@rustbot``` label O-apple

src/tools/run-make-support/src/lib.rs

@@ -73,7 +73,7 @@ pub use env::{env_var, env_var_os, set_current_dir};
 pub use run::{cmd, run, run_fail, run_with_args};
 
 /// Helpers for checking target information.
-pub use targets::{is_darwin, is_msvc, is_windows, llvm_components_contain, target, uname};
+pub use targets::{is_darwin, is_msvc, is_windows, llvm_components_contain, target, uname, apple_os};
 
 /// Helpers for building names of output artifacts that are potentially target-specific.
 pub use artifact_names::{

src/tools/run-make-support/src/targets.rs

@@ -28,6 +28,24 @@ pub fn is_darwin() -> bool {
     target().contains("darwin")
 }
 
+/// Get the target OS on Apple operating systems.
+#[must_use]
+pub fn apple_os() -> &'static str {
+    if target().contains("darwin") {
+        "macos"
+    } else if target().contains("ios") {
+        "ios"
+    } else if target().contains("tvos") {
+        "tvos"
+    } else if target().contains("watchos") {
+        "watchos"
+    } else if target().contains("visionos") {
+        "visionos"
+    } else {
+        panic!("not an Apple OS")
+    }
+}
+
 /// Check if `component` is within `LLVM_COMPONENTS`
 #[must_use]
 pub fn llvm_components_contain(component: &str) -> bool {

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -6,7 +6,6 @@ run-make/incr-add-rust-src-component/Makefile
 run-make/issue-84395-lto-embed-bitcode/Makefile
 run-make/jobserver-error/Makefile
 run-make/libs-through-symlinks/Makefile
-run-make/macos-deployment-target/Makefile
 run-make/split-debuginfo/Makefile
 run-make/symbol-mangling-hashed/Makefile
 run-make/translation/Makefile

tests/run-make/apple-deployment-target/foo.rs

@@ -0,0 +1 @@
+fn main() {}

tests/run-make/apple-deployment-target/rmake.rs

@@ -0,0 +1,157 @@
+//! Test codegen when setting deployment targets on Apple platforms.
+//!
+//! This is important since its a compatibility hazard. The linker will
+//! generate load commands differently based on what minimum OS it can assume.
+//!
+//! See https://github.com/rust-lang/rust/pull/105123.
+
+//@ only-apple
+
+use run_make_support::{apple_os, cmd, run_in_tmpdir, rustc, target};
+
+/// Run vtool to check the `minos` field in LC_BUILD_VERSION.
+///
+/// On lower deployment targets, LC_VERSION_MIN_MACOSX, LC_VERSION_MIN_IPHONEOS and similar
+/// are used instead of LC_BUILD_VERSION - these have a `version` field, so also check that.
+#[track_caller]
+fn minos(file: &str, version: &str) {
+    cmd("vtool")
+        .arg("-show-build")
+        .arg(file)
+        .run()
+        .assert_stdout_contains_regex(format!("(minos|version) {version}"));
+}
+
+fn main() {
+    // These versions should generally be higher than the default versions
+    let (env_var, example_version, higher_example_version) = match apple_os() {
+        "macos" => ("MACOSX_DEPLOYMENT_TARGET", "12.0", "13.0"),
+        // armv7s-apple-ios and i386-apple-ios only supports iOS 10.0
+        "ios" if target() == "armv7s-apple-ios" || target() == "i386-apple-ios" => {
+            ("IPHONEOS_DEPLOYMENT_TARGET", "10.0", "10.0")
+        }
+        "ios" => ("IPHONEOS_DEPLOYMENT_TARGET", "15.0", "16.0"),
+        "watchos" => ("WATCHOS_DEPLOYMENT_TARGET", "7.0", "9.0"),
+        "tvos" => ("TVOS_DEPLOYMENT_TARGET", "14.0", "15.0"),
+        "visionos" => ("XROS_DEPLOYMENT_TARGET", "1.1", "1.2"),
+        _ => unreachable!(),
+    };
+    let default_version =
+        rustc().target(target()).env_remove(env_var).print("deployment-target").run().stdout_utf8();
+    let default_version = default_version.strip_prefix("deployment_target=").unwrap().trim();
+
+    // Test that version makes it to the object file.
+    run_in_tmpdir(|| {
+        let rustc = || {
+            let mut rustc = rustc();
+            rustc.target(target());
+            rustc.crate_type("lib");
+            rustc.emit("obj");
+            rustc.input("foo.rs");
+            rustc.output("foo.o");
+            rustc
+        };
+
+        rustc().env(env_var, example_version).run();
+        minos("foo.o", example_version);
+
+        // FIXME(madsmtm): Doesn't work on Mac Catalyst and the simulator.
+        if !target().contains("macabi") && !target().contains("sim") {
+            rustc().env_remove(env_var).run();
+            minos("foo.o", default_version);
+        }
+    });
+
+    // Test that version makes it to the linker when linking dylibs.
+    run_in_tmpdir(|| {
+        // Certain watchOS targets don't support dynamic linking, so we disable the test on those.
+        if apple_os() == "watchos" {
+            return;
+        }
+
+        let rustc = || {
+            let mut rustc = rustc();
+            rustc.target(target());
+            rustc.crate_type("dylib");
+            rustc.input("foo.rs");
+            rustc.output("libfoo.dylib");
+            rustc
+        };
+
+        rustc().env(env_var, example_version).run();
+        minos("libfoo.dylib", example_version);
+
+        // FIXME(madsmtm): Deployment target is not currently passed properly to linker
+        // rustc().env_remove(env_var).run();
+        // minos("libfoo.dylib", default_version);
+
+        // Test with ld64 instead
+
+        rustc().arg("-Clinker-flavor=ld").env(env_var, example_version).run();
+        minos("libfoo.dylib", example_version);
+
+        rustc().arg("-Clinker-flavor=ld").env_remove(env_var).run();
+        minos("libfoo.dylib", default_version);
+    });
+
+    // Test that version makes it to the linker when linking executables.
+    run_in_tmpdir(|| {
+        let rustc = || {
+            let mut rustc = rustc();
+            rustc.target(target());
+            rustc.crate_type("bin");
+            rustc.input("foo.rs");
+            rustc.output("foo");
+            rustc
+        };
+
+        // FIXME(madsmtm): Doesn't work on watchOS for some reason?
+        if !target().contains("watchos") {
+            rustc().env(env_var, example_version).run();
+            minos("foo", example_version);
+
+            // FIXME(madsmtm): Deployment target is not currently passed properly to linker
+            // rustc().env_remove(env_var).run();
+            // minos("foo", default_version);
+        }
+
+        // Test with ld64 instead
+
+        rustc().arg("-Clinker-flavor=ld").env(env_var, example_version).run();
+        minos("foo", example_version);
+
+        rustc().arg("-Clinker-flavor=ld").env_remove(env_var).run();
+        minos("foo", default_version);
+    });
+
+    // Test that changing the deployment target busts the incremental cache.
+    run_in_tmpdir(|| {
+        let rustc = || {
+            let mut rustc = rustc();
+            rustc.target(target());
+            rustc.incremental("incremental");
+            rustc.crate_type("lib");
+            rustc.emit("obj");
+            rustc.input("foo.rs");
+            rustc.output("foo.o");
+            rustc
+        };
+
+        // FIXME(madsmtm): Incremental cache is not yet busted
+        // https://github.com/rust-lang/rust/issues/118204
+        let higher_example_version = example_version;
+        let default_version = example_version;
+
+        rustc().env(env_var, example_version).run();
+        minos("foo.o", example_version);
+
+        rustc().env(env_var, higher_example_version).run();
+        minos("foo.o", higher_example_version);
+
+        // FIXME(madsmtm): Doesn't work on Mac Catalyst and the simulator.
+        if !target().contains("macabi") && !target().contains("sim") {
+            rustc().env_remove(env_var).run();
+            minos("foo.o", default_version);
+        }
+    });
+}