Add z/OS target

src/host.rs

@@ -41,6 +41,13 @@ mod tests {
         assert_eq!(OperatingSystem::host(), OperatingSystem::Windows);
     }
 
+    #[cfg(target_os = "zos")]
+    #[test]
+    fn test_zos() {
+        use super::*;
+        assert_eq!(OperatingSystem::host(), OperatingSystem::Zos);
+    }
+
     #[cfg(target_pointer_width = "16")]
     #[test]
     fn test_ptr16() {

src/targets.rs

@@ -758,6 +758,7 @@ pub enum OperatingSystem {
     Windows,
     /// An alternate name for [visionOS][Self::VisionOS].
     XROS(Option<DeploymentTarget>),
+    Zos,
 }
 
 impl OperatingSystem {
@@ -819,6 +820,7 @@ impl OperatingSystem {
             WatchOS(deployment_target) => darwin_version("watchos", deployment_target),
             Windows => Cow::Borrowed("windows"),
             XROS(deployment_target) => darwin_version("xros", deployment_target),
+            Zos => Cow::Borrowed("zos"),
         }
     }
 
@@ -943,6 +945,7 @@ pub enum BinaryFormat {
     Macho,
     Wasm,
     Xcoff,
+    Goff,
 }
 
 impl BinaryFormat {
@@ -957,6 +960,7 @@ impl BinaryFormat {
             Macho => Cow::Borrowed("macho"),
             Wasm => Cow::Borrowed("wasm"),
             Xcoff => Cow::Borrowed("xcoff"),
+            Goff => Cow::Borrowed("goff"),
         }
     }
 }
@@ -1133,6 +1137,7 @@ pub(crate) fn default_binary_format(triple: &Triple) -> BinaryFormat {
         OperatingSystem::Aix => BinaryFormat::Xcoff,
         os if os.is_like_darwin() => BinaryFormat::Macho,
         OperatingSystem::Windows => BinaryFormat::Coff,
+        OperatingSystem::Zos => BinaryFormat::Goff,
         OperatingSystem::Nebulet
         | OperatingSystem::Emscripten
         | OperatingSystem::VxWorks
@@ -1667,6 +1672,7 @@ impl FromStr for OperatingSystem {
             "wasip1" => WasiP1,
             "wasip2" => WasiP2,
             "windows" => Windows,
+            "zos" => Zos,
             "espidf" => Espidf,
             _ => return Err(()),
         })
@@ -1745,6 +1751,7 @@ impl FromStr for BinaryFormat {
             "macho" => Macho,
             "wasm" => Wasm,
             "xcoff" => Xcoff,
+            "goff" => Goff,
             _ => return Err(()),
         })
     }
@@ -1949,6 +1956,7 @@ mod tests {
             "riscv64gc-unknown-openbsd",
             "riscv64imac-unknown-none-elf",
             "riscv64-linux-android",
+            "s390x-ibm-zos",
             "s390x-unknown-linux-gnu",
             "s390x-unknown-linux-musl",
             "sparc64-unknown-linux-gnu",

src/triple.rs

@@ -76,6 +76,10 @@ pub enum CallingConvention {
     ///
     /// <https://developer.apple.com/documentation/xcode/writing_arm64_code_for_apple_platforms>
     AppleAarch64,
+
+    /// IBM z/OS XPLINK CALL linkage conventions for AMODE 64 applications
+    /// https://www.ibm.com/docs/en/zos/3.1.0?topic=applications-xplink-call-linkage-conventions-amode-64
+    ZosXplink64,
 }
 
 /// An LLVM target "triple". Historically such things had three fields, though
@@ -141,6 +145,7 @@ impl Triple {
             | OperatingSystem::Redox
             | OperatingSystem::Solaris => CallingConvention::SystemV,
             OperatingSystem::Windows => CallingConvention::WindowsFastcall,
+            OperatingSystem::Zos => CallingConvention::ZosXplink64,
             OperatingSystem::Nebulet
             | OperatingSystem::Emscripten
             | OperatingSystem::Wasi