Fix building for Mac Catalyst (#1577)

Without this change, we end up passing `aarch64-apple-ios26.0-macabimacabi` to the compiler, which is definitely wrong.

The core change here is to handle this in `from_cargo_environment_variables` as well, the rest is just a cleanup now that `target.env` contains the canonical value (and `target.abi`).

See also the previous #1517 and #1534.

Author: madsmtm

src/lib.rs

@@ -2248,12 +2248,11 @@ impl Build {
                     // So instead, we pass the deployment target with `-m*-version-min=`, and only
                     // pass it here on visionOS and Mac Catalyst where that option does not exist:
                     // https://github.com/rust-lang/cc-rs/issues/1383
-                    let version =
-                        if target.os == "visionos" || target.get_apple_env() == Some(MacCatalyst) {
-                            Some(self.apple_deployment_target(target))
-                        } else {
-                            None
-                        };
+                    let version = if target.os == "visionos" || target.env == "macabi" {
+                        Some(self.apple_deployment_target(target))
+                    } else {
+                        None
+                    };
 
                     let clang_target =
                         target.llvm_target(&self.get_raw_target()?, version.as_deref());
@@ -2746,9 +2745,7 @@ impl Build {
         // https://github.com/llvm/llvm-project/issues/88271
         // And the workaround to use `-mtargetos=` cannot be used with the `--target` flag that we
         // otherwise specify. So we avoid emitting that, and put the version in `--target` instead.
-        if cmd.is_like_gnu()
-            || !(target.os == "visionos" || target.get_apple_env() == Some(MacCatalyst))
-        {
+        if cmd.is_like_gnu() || !(target.os == "visionos" || target.env == "macabi") {
             let min_version = self.apple_deployment_target(&target);
             cmd.args
                 .push(target.apple_version_flag(&min_version).into());
@@ -2768,7 +2765,7 @@ impl Build {
             cmd.env
                 .push(("SDKROOT".into(), OsStr::new(&sdk_path).to_owned()));
 
-            if target.get_apple_env() == Some(MacCatalyst) {
+            if target.env == "macabi" {
                 // Mac Catalyst uses the macOS SDK, but to compile against and
                 // link to iOS-specific frameworks, we should have the support
                 // library stubs in the include and library search path.

src/target.rs

@@ -6,7 +6,6 @@ mod generated;
 mod llvm;
 mod parser;
 
-pub(crate) use apple::*;
 pub(crate) use parser::TargetInfoParser;
 
 /// Information specific to a `rustc` target.

src/target/apple.rs

@@ -1,33 +1,18 @@
 use super::TargetInfo;
 
-#[derive(Copy, Clone, Debug, Eq, PartialEq)]
-pub(crate) enum AppleEnv {
-    Simulator,
-    MacCatalyst,
-}
-pub(crate) use AppleEnv::*;
-
 impl TargetInfo<'_> {
-    pub(crate) fn get_apple_env(&self) -> Option<AppleEnv> {
-        match (self.env, self.abi) {
-            ("sim", _) | (_, "sim") => Some(Simulator),
-            ("macabi", _) | (_, "macabi") => Some(MacCatalyst),
-            _ => None,
-        }
-    }
-
     pub(crate) fn apple_sdk_name(&self) -> &'static str {
-        match (self.os, self.get_apple_env()) {
-            ("macos", None) => "macosx",
-            ("ios", None) => "iphoneos",
-            ("ios", Some(Simulator)) => "iphonesimulator",
-            ("ios", Some(MacCatalyst)) => "macosx",
-            ("tvos", None) => "appletvos",
-            ("tvos", Some(Simulator)) => "appletvsimulator",
-            ("watchos", None) => "watchos",
-            ("watchos", Some(Simulator)) => "watchsimulator",
-            ("visionos", None) => "xros",
-            ("visionos", Some(Simulator)) => "xrsimulator",
+        match (self.os, self.env) {
+            ("macos", "") => "macosx",
+            ("ios", "") => "iphoneos",
+            ("ios", "sim") => "iphonesimulator",
+            ("ios", "macabi") => "macosx",
+            ("tvos", "") => "appletvos",
+            ("tvos", "sim") => "appletvsimulator",
+            ("watchos", "") => "watchos",
+            ("watchos", "sim") => "watchsimulator",
+            ("visionos", "") => "xros",
+            ("visionos", "sim") => "xrsimulator",
             (os, _) => panic!("invalid Apple target OS {}", os),
         }
     }
@@ -45,19 +30,19 @@ impl TargetInfo<'_> {
         // https://clang.llvm.org/docs/ClangCommandLineReference.html#cmdoption-clang-mmacos-version-min
         // https://clang.llvm.org/docs/AttributeReference.html#availability
         // https://gcc.gnu.org/onlinedocs/gcc/Darwin-Options.html#index-mmacosx-version-min
-        match (self.os, self.get_apple_env()) {
-            ("macos", None) => format!("-mmacosx-version-min={min_version}"),
-            ("ios", None) => format!("-miphoneos-version-min={min_version}"),
-            ("ios", Some(Simulator)) => format!("-mios-simulator-version-min={min_version}"),
-            ("ios", Some(MacCatalyst)) => format!("-mtargetos=ios{min_version}-macabi"),
-            ("tvos", None) => format!("-mappletvos-version-min={min_version}"),
-            ("tvos", Some(Simulator)) => format!("-mappletvsimulator-version-min={min_version}"),
-            ("watchos", None) => format!("-mwatchos-version-min={min_version}"),
-            ("watchos", Some(Simulator)) => format!("-mwatchsimulator-version-min={min_version}"),
+        match (self.os, self.env) {
+            ("macos", "") => format!("-mmacosx-version-min={min_version}"),
+            ("ios", "") => format!("-miphoneos-version-min={min_version}"),
+            ("ios", "sim") => format!("-mios-simulator-version-min={min_version}"),
+            ("ios", "macabi") => format!("-mtargetos=ios{min_version}-macabi"),
+            ("tvos", "") => format!("-mappletvos-version-min={min_version}"),
+            ("tvos", "sim") => format!("-mappletvsimulator-version-min={min_version}"),
+            ("watchos", "") => format!("-mwatchos-version-min={min_version}"),
+            ("watchos", "sim") => format!("-mwatchsimulator-version-min={min_version}"),
             // `-mxros-version-min` does not exist
             // https://github.com/llvm/llvm-project/issues/88271
-            ("visionos", None) => format!("-mtargetos=xros{min_version}"),
-            ("visionos", Some(Simulator)) => format!("-mtargetos=xros{min_version}-simulator"),
+            ("visionos", "") => format!("-mtargetos=xros{min_version}"),
+            ("visionos", "sim") => format!("-mtargetos=xros{min_version}-simulator"),
             (os, _) => panic!("invalid Apple target OS {}", os),
         }
     }

src/target/llvm.rs

@@ -95,13 +95,6 @@ impl TargetInfo<'_> {
             env => env,
         };
         let abi = match self.abi {
-            "sim" => {
-                if env != "simulator" {
-                    "simulator"
-                } else {
-                    ""
-                }
-            }
             "llvm" | "softfloat" | "uwp" | "vec-extabi" => "",
             "ilp32" => "_ilp32",
             "abi64" => "",
@@ -198,8 +191,8 @@ mod tests {
                 arch: "aarch64",
                 vendor: "apple",
                 os: "ios",
-                env: "",
-                abi: "sim",
+                env: "sim",
+                abi: "",
             }
             .llvm_target("aarch64-apple-ios-sim", Some("14.0")),
             "arm64-apple-ios14.0-simulator"

src/target/parser.rs

@@ -1,4 +1,4 @@
-use std::env;
+use std::{env, mem};
 
 use crate::{target::TargetInfo, utilities::OnceLock, Error, ErrorKind};
 
@@ -67,13 +67,25 @@ impl TargetInfoParserInner {
         let arch = cargo_env("CARGO_CFG_TARGET_ARCH", ft.map(|t| t.arch))?;
         let vendor = cargo_env("CARGO_CFG_TARGET_VENDOR", ft.map(|t| t.vendor))?;
         let os = cargo_env("CARGO_CFG_TARGET_OS", ft.map(|t| t.os))?;
-        let env = cargo_env("CARGO_CFG_TARGET_ENV", ft.map(|t| t.env))?;
+        let mut env = cargo_env("CARGO_CFG_TARGET_ENV", ft.map(|t| t.env))?;
         // `target_abi` was stabilized in Rust 1.78, which is higher than our
         // MSRV, so it may not always be available; In that case, fall back to
         // `""`, which is _probably_ correct for unknown target names.
-        let abi = cargo_env("CARGO_CFG_TARGET_ABI", ft.map(|t| t.abi))
+        let mut abi = cargo_env("CARGO_CFG_TARGET_ABI", ft.map(|t| t.abi))
             .unwrap_or_else(|_| String::default().into_boxed_str());
 
+        // Remove `macabi` and `sim` from `target_abi` (if present), it's been moved to `target_env`.
+        // TODO: Remove once MSRV is bumped to 1.91 and `rustc` removes these from `target_abi`.
+        if matches!(&*abi, "macabi" | "sim") {
+            debug_assert!(
+                matches!(&*env, "" | "macbi" | "sim"),
+                "env/abi mismatch: {:?}, {:?}",
+                env,
+                abi,
+            );
+            env = mem::replace(&mut abi, String::default().into_boxed_str());
+        }
+
         Ok(Self {
             full_arch: full_arch.to_string().into_boxed_str(),
             arch,
@@ -597,4 +609,30 @@ mod tests {
             panic!("failed comparing targets");
         }
     }
+
+    #[test]
+    fn parses_apple_envs_correctly() {
+        assert_eq!(
+            TargetInfo::from_rustc_target("aarch64-apple-ios-macabi").unwrap(),
+            TargetInfo {
+                full_arch: "aarch64",
+                arch: "aarch64",
+                vendor: "apple",
+                os: "ios",
+                env: "macabi",
+                abi: "",
+            }
+        );
+        assert_eq!(
+            TargetInfo::from_rustc_target("aarch64-apple-ios-sim").unwrap(),
+            TargetInfo {
+                full_arch: "aarch64",
+                arch: "aarch64",
+                vendor: "apple",
+                os: "ios",
+                env: "sim",
+                abi: "",
+            }
+        );
+    }
 }