Rollup merge of #104622 - nicholasbishop:bishop-uefi-clang, r=Mark-Simulacrum

Use clang for the UEFI targets

This fixes an issue where the C and asm sources built by compiler_builtins were being compiled as ELF objects instead of PE objects. This wasn't noticed before because it doesn't cause compiler_builtins or rustc to fail to build. You only see a failure when a program is built that references one of the symbols in an ELF object.

Compiling with clang fixes this because the cc crate converts the UEFI targets into Windows targets that clang understands, causing it to produce PE objects.

Also update compiler_builtins to 0.1.84 to pull in some necessary fixes for compiling the UEFI targets with clang.

Fixes https://github.com/rust-lang/rust/issues/104326

5 files changed, 59 insertions, 1 deletions

diff --git a/src/bootstrap/Cargo.lock b/src/bootstrap/Cargo.lock
index a59dc4f87a6..0cd778a0cbb 100644
--- a/src/bootstrap/Cargo.lock
+++ b/src/bootstrap/Cargo.lock
@@ -53,6 +53,7 @@ dependencies = [
  "hex",
  "ignore",
  "libc",
+ "object",
  "once_cell",
  "opener",
  "pretty_assertions",
@@ -401,6 +402,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "object"
+version = "0.29.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "21158b2c33aa6d4561f1c0a6ea283ca92bc54802a93b263e910746d679a7eb53"
+dependencies = [
+ "memchr",
+]
+
+[[package]]
 name = "once_cell"
 version = "1.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/src/bootstrap/Cargo.toml b/src/bootstrap/Cargo.toml
index 813c8075605..4c24c214d2c 100644
--- a/src/bootstrap/Cargo.toml
+++ b/src/bootstrap/Cargo.toml
@@ -42,6 +42,7 @@ getopts = "0.2.19"
 cc = "1.0.69"
 libc = "0.2"
 hex = "0.4"
+object = { version = "0.29.0", default-features = false, features = ["archive", "coff", "read_core", "unaligned"] }
 serde = { version = "1.0.8", features = ["derive"] }
 serde_json = "1.0.2"
 sha2 = "0.10"
diff --git a/src/bootstrap/dist.rs b/src/bootstrap/dist.rs
index aacd2c7eab9..2fef7f65827 100644
--- a/src/bootstrap/dist.rs
+++ b/src/bootstrap/dist.rs
@@ -10,10 +10,14 @@
 
 use std::collections::HashSet;
 use std::env;
+use std::ffi::OsStr;
 use std::fs;
 use std::path::{Path, PathBuf};
 use std::process::Command;
 
+use object::read::archive::ArchiveFile;
+use object::BinaryFormat;
+
 use crate::builder::{Builder, Kind, RunConfig, ShouldRun, Step};
 use crate::cache::{Interned, INTERNER};
 use crate::channel;
@@ -555,6 +559,39 @@ fn skip_host_target_lib(builder: &Builder<'_>, compiler: Compiler) -> bool {
     }
 }
 
+/// Check that all objects in rlibs for UEFI targets are COFF. This
+/// ensures that the C compiler isn't producing ELF objects, which would
+/// not link correctly with the COFF objects.
+fn verify_uefi_rlib_format(builder: &Builder<'_>, target: TargetSelection, stamp: &Path) {
+    if !target.ends_with("-uefi") {
+        return;
+    }
+
+    for (path, _) in builder.read_stamp_file(stamp) {
+        if path.extension() != Some(OsStr::new("rlib")) {
+            continue;
+        }
+
+        let data = t!(fs::read(&path));
+        let data = data.as_slice();
+        let archive = t!(ArchiveFile::parse(data));
+        for member in archive.members() {
+            let member = t!(member);
+            let member_data = t!(member.data(data));
+
+            let is_coff = match object::File::parse(member_data) {
+                Ok(member_file) => member_file.format() == BinaryFormat::Coff,
+                Err(_) => false,
+            };
+
+            if !is_coff {
+                let member_name = String::from_utf8_lossy(member.name());
+                panic!("member {} in {} is not COFF", member_name, path.display());
+            }
+        }
+    }
+}
+
 /// Copy stamped files into an image's `target/lib` directory.
 fn copy_target_libs(builder: &Builder<'_>, target: TargetSelection, image: &Path, stamp: &Path) {
     let dst = image.join("lib/rustlib").join(target.triple).join("lib");
@@ -610,6 +647,7 @@ impl Step for Std {
 
         let compiler_to_use = builder.compiler_for(compiler.stage, compiler.host, target);
         let stamp = compile::libstd_stamp(builder, compiler_to_use, target);
+        verify_uefi_rlib_format(builder, target, &stamp);
         copy_target_libs(builder, target, &tarball.image_dir(), &stamp);
 
         Some(tarball.generate())
diff --git a/src/ci/docker/host-x86_64/dist-various-2/Dockerfile b/src/ci/docker/host-x86_64/dist-various-2/Dockerfile
index e1adabaac9b..93ef7dfcbf5 100644
--- a/src/ci/docker/host-x86_64/dist-various-2/Dockerfile
+++ b/src/ci/docker/host-x86_64/dist-various-2/Dockerfile
@@ -61,6 +61,12 @@ ENV \
     AR_i686_unknown_freebsd=i686-unknown-freebsd12-ar \
     CC_i686_unknown_freebsd=i686-unknown-freebsd12-clang \
     CXX_i686_unknown_freebsd=i686-unknown-freebsd12-clang++ \
+    CC_aarch64_unknown_uefi=clang-11 \
+    CXX_aarch64_unknown_uefi=clang++-11 \
+    CC_i686_unknown_uefi=clang-11 \
+    CXX_i686_unknown_uefi=clang++-11 \
+    CC_x86_64_unknown_uefi=clang-11 \
+    CXX_x86_64_unknown_uefi=clang++-11 \
     CC=gcc-8 \
     CXX=g++-8
 
diff --git a/src/ci/docker/host-x86_64/test-various/Dockerfile b/src/ci/docker/host-x86_64/test-various/Dockerfile
index b0f35bcb9cc..0bddffa3436 100644
--- a/src/ci/docker/host-x86_64/test-various/Dockerfile
+++ b/src/ci/docker/host-x86_64/test-various/Dockerfile
@@ -1,6 +1,7 @@
 FROM ubuntu:20.04
 
 RUN apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
+  clang-11 \
   g++ \
   make \
   ninja-build \
@@ -67,7 +68,9 @@ ENV MUSL_TARGETS=x86_64-unknown-linux-musl \
 ENV MUSL_SCRIPT python3 /checkout/x.py --stage 2 test --host='' --target $MUSL_TARGETS
 
 COPY host-x86_64/test-various/uefi_qemu_test /uefi_qemu_test
-ENV UEFI_TARGETS=x86_64-unknown-uefi
+ENV UEFI_TARGETS=x86_64-unknown-uefi \
+    CC_x86_64_unknown_uefi=clang-11 \
+    CXX_x86_64_unknown_uefi=clang++-11
 ENV UEFI_SCRIPT python3 /checkout/x.py --stage 2 build --host='' --target $UEFI_TARGETS && \
   python3 -u /uefi_qemu_test/run.py