Add support for powerpc-unknown-freebsd

Author: pkubaj

Diff for: compiler/rustc_target/src/spec/mod.rs

@@ -802,6 +802,7 @@ supported_targets! {
     ("armv6-unknown-freebsd", armv6_unknown_freebsd),
     ("armv7-unknown-freebsd", armv7_unknown_freebsd),
     ("i686-unknown-freebsd", i686_unknown_freebsd),
+    ("powerpc-unknown-freebsd", powerpc_unknown_freebsd),
     ("powerpc64-unknown-freebsd", powerpc64_unknown_freebsd),
     ("powerpc64le-unknown-freebsd", powerpc64le_unknown_freebsd),
     ("x86_64-unknown-freebsd", x86_64_unknown_freebsd),

Diff for: compiler/rustc_target/src/spec/powerpc_unknown_freebsd.rs

@@ -0,0 +1,27 @@
+use crate::abi::Endian;
+use crate::spec::{LinkerFlavor, RelocModel, Target, TargetOptions};
+
+pub fn target() -> Target {
+    let mut base = super::freebsd_base::opts();
+    base.pre_link_args.entry(LinkerFlavor::Gcc).or_default().push("-m32".to_string());
+    // Extra hint to linker that we are generating secure-PLT code.
+    base.pre_link_args
+        .entry(LinkerFlavor::Gcc)
+        .or_default()
+        .push("--target=powerpc-unknown-freebsd13.0".to_string());
+    base.max_atomic_width = Some(32);
+
+    Target {
+        llvm_target: "powerpc-unknown-freebsd13.0".to_string(),
+        pointer_width: 32,
+        data_layout: "E-m:e-p:32:32-i64:64-n32".to_string(),
+        arch: "powerpc".to_string(),
+        options: TargetOptions {
+            endian: Endian::Big,
+            features: "+secure-plt".to_string(),
+            relocation_model: RelocModel::Pic,
+            mcount: "_mcount".to_string(),
+            ..base
+        },
+    }
+}

Diff for: src/bootstrap/native.rs

@@ -118,6 +118,10 @@ impl Step for Llvm {
             let idx = target.triple.find('-').unwrap();
 
             format!("riscv{}{}", &target.triple[5..7], &target.triple[idx..])
+        } else if self.target.starts_with("powerpc") && self.target.ends_with("freebsd") {
+            // FreeBSD 13 had incompatible ABI changes on all PowerPC platforms.
+            // Set the version suffix to 13.0 so the correct target details are used.
+            format!("{}{}", self.target, "13.0")
         } else {
             target.to_string()
         };
@@ -277,6 +281,11 @@ impl Step for Llvm {
             }
         }
 
+        // Workaround for ppc32 lld limitation
+        if target == "powerpc-unknown-freebsd" {
+            cfg.define("CMAKE_EXE_LINKER_FLAGS", "-fuse-ld=bfd");
+        }
+
         // https://llvm.org/docs/HowToCrossCompileLLVM.html
         if target != builder.config.build {
             builder.ensure(Llvm { target: builder.config.build });

Diff for: src/doc/rustc/src/platform-support.md

@@ -249,6 +249,7 @@ target | std | host | notes
 `powerpc-wrs-vxworks` | ? |  |
 `powerpc64-unknown-freebsd` | ✓ | ✓ | PPC64 FreeBSD (ELFv1 and ELFv2)
 `powerpc64le-unknown-freebsd` |   |   | PPC64LE FreeBSD
+`powerpc-unknown-freebsd` |   |   | PowerPC FreeBSD
 `powerpc64-unknown-linux-musl` | ? |  |
 `powerpc64-wrs-vxworks` | ? |  |
 `powerpc64le-unknown-linux-musl` | ? |  |