diff --git a/compiler/rustc_codegen_gcc/.github/workflows/m68k.yml b/compiler/rustc_codegen_gcc/.github/workflows/m68k.yml
index 245bee7f2a3bd..759d0d59e2685 100644
--- a/compiler/rustc_codegen_gcc/.github/workflows/m68k.yml
+++ b/compiler/rustc_codegen_gcc/.github/workflows/m68k.yml
@@ -14,8 +14,6 @@ permissions:
 env:
   # Enable backtraces for easier debugging
   RUST_BACKTRACE: 1
-  # TODO: remove when confish.sh is removed.
-  OVERWRITE_TARGET_TRIPLE: m68k-unknown-linux-gnu
 
 jobs:
   build:
@@ -59,14 +57,12 @@ jobs:
 
     - name: Setup path to libgccjit
       run: |
-          sudo dpkg -i gcc-m68k-15.deb
+          sudo dpkg --force-overwrite -i gcc-m68k-15.deb
           echo 'gcc-path = "/usr/lib/"' > config.toml
 
     - name: Set env
       run: |
         echo "workspace="$GITHUB_WORKSPACE >> $GITHUB_ENV
-        
-        
 
     #- name: Cache rust repository
       ## We only clone the rust repository for rustc tests
@@ -86,16 +82,20 @@ jobs:
     - name: Build sample project with target defined as JSON spec
       run: |
         ./y.sh prepare --only-libcore --cross
-        ./y.sh build --sysroot --features compiler_builtins/no-f16-f128 --target-triple m68k-unknown-linux-gnu --target ${{ github.workspace }}/target_specs/m68k-unknown-linux-gnu.json
-        ./y.sh cargo build --manifest-path=./tests/hello-world/Cargo.toml --target ${{ github.workspace }}/target_specs/m68k-unknown-linux-gnu.json
+        ./y.sh build --sysroot --features compiler-builtins-no-f16-f128 --target-triple m68k-unknown-linux-gnu --target ${{ github.workspace }}/target_specs/m68k-unknown-linux-gnu.json
+        CG_RUSTFLAGS="-Clinker=m68k-unknown-linux-gnu-gcc" ./y.sh cargo build --manifest-path=./tests/hello-world/Cargo.toml --target ${{ github.workspace }}/target_specs/m68k-unknown-linux-gnu.json
         ./y.sh clean all
 
     - name: Build
       run: |
         ./y.sh prepare --only-libcore --cross
-        ./y.sh build --sysroot --features compiler_builtins/no-f16-f128 --target-triple m68k-unknown-linux-gnu
-        ./y.sh test --mini-tests
-        CG_GCC_TEST_TARGET=m68k-unknown-linux-gnu ./y.sh test --cargo-tests
+        ./y.sh build --sysroot --features compiler-builtins-no-f16-f128 --target-triple m68k-unknown-linux-gnu
+        ./y.sh test --mini-tests --target-triple m68k-unknown-linux-gnu
+        # FIXME: since https://github.com/rust-lang/rust/pull/140809, we cannot run programs for architectures not
+        # supported by the object crate, since this adds a dependency on symbols.o for the panic runtime.
+        # And as such, a wrong order of the object files in the linker command now fails with an undefined reference
+        # to some symbols like __rustc::rust_panic.
+        #CG_GCC_TEST_TARGET=m68k-unknown-linux-gnu ./y.sh test --cargo-tests --target-triple m68k-unknown-linux-gnu
         ./y.sh clean all
 
     - name: Prepare dependencies
@@ -104,9 +104,23 @@ jobs:
         git config --global user.name "User"
         ./y.sh prepare --cross
 
-    - name: Run tests
-      run: |
-        ./y.sh test --release --clean --build-sysroot --sysroot-features compiler_builtins/no-f16-f128 ${{ matrix.commands }}
+    # FIXME: We cannot run programs for architectures not supported by the object crate. See comment above.
+    #- name: Run tests
+      #run: |
+        #./y.sh test --target-triple m68k-unknown-linux-gnu --release --clean --build-sysroot --sysroot-features compiler-builtins-no-f16-f128 ${{ matrix.commands }}
+
+    # FIXME: We cannot run programs for architectures not supported by the object crate. See comment above.
+    #- name: Run Hello World!
+      #run: |
+        #./y.sh build --target-triple m68k-unknown-linux-gnu
+
+        #vm_dir=$(pwd)/vm
+        #cd tests/hello-world
+        #CG_RUSTFLAGS="-Clinker=m68k-unknown-linux-gnu-gcc" ../../y.sh cargo build --target m68k-unknown-linux-gnu
+        #sudo cp target/m68k-unknown-linux-gnu/debug/hello_world $vm_dir/home/
+        #sudo chroot $vm_dir qemu-m68k-static /home/hello_world > hello_world_stdout
+        #expected_output="40"
+        #test $(cat hello_world_stdout) == $expected_output || (echo "Output differs. Actual output: $(cat hello_world_stdout)"; exit 1)
 
   # Summary job for the merge queue.
   # ALL THE PREVIOUS JOBS NEED TO BE ADDED TO THE `needs` SECTION OF THIS JOB!
diff --git a/compiler/rustc_codegen_gcc/.github/workflows/release.yml b/compiler/rustc_codegen_gcc/.github/workflows/release.yml
index 1d8eaf9a141f6..b7e2583aad39f 100644
--- a/compiler/rustc_codegen_gcc/.github/workflows/release.yml
+++ b/compiler/rustc_codegen_gcc/.github/workflows/release.yml
@@ -78,7 +78,8 @@ jobs:
     - name: Run tests
       run: |
         # FIXME(antoyo): we cannot enable LTO for stdarch tests currently because of some failing LTO tests using proc-macros.
-        echo -n 'lto = "fat"' >> build_system/build_sysroot/Cargo.toml
+        # FIXME(antoyo): this should probably not be needed since we embed the LTO bitcode.
+        printf '[profile.release]\nlto = "fat"\n' >> build/build_sysroot/sysroot_src/library/Cargo.toml
         EMBED_LTO_BITCODE=1 ./y.sh test --release --clean --release-sysroot --build-sysroot --keep-lto-tests ${{ matrix.commands }}
 
     - name: Run y.sh cargo build
diff --git a/compiler/rustc_codegen_gcc/build_system/build_sysroot/Cargo.lock b/compiler/rustc_codegen_gcc/build_system/build_sysroot/Cargo.lock
deleted file mode 100644
index 0c75977ee7989..0000000000000
--- a/compiler/rustc_codegen_gcc/build_system/build_sysroot/Cargo.lock
+++ /dev/null
@@ -1,502 +0,0 @@
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diff --git a/compiler/rustc_codegen_gcc/build_system/build_sysroot/Cargo.toml b/compiler/rustc_codegen_gcc/build_system/build_sysroot/Cargo.toml
deleted file mode 100644
index 29a3bcec304c8..0000000000000
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+++ /dev/null
@@ -1,39 +0,0 @@
-[package]
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-[dependencies]
-core = { path = "./sysroot_src/library/core" }
-compiler_builtins = { path = "./sysroot_src/library/compiler-builtins/compiler-builtins" }
-alloc = { path = "./sysroot_src/library/alloc" }
-std = { path = "./sysroot_src/library/std", features = ["panic_unwind", "backtrace"] }
-test = { path = "./sysroot_src/library/test" }
-proc_macro = { path = "./sysroot_src/library/proc_macro" }
-
-[patch.crates-io]
-rustc-std-workspace-core = { path = "./sysroot_src/library/rustc-std-workspace-core" }
-rustc-std-workspace-alloc = { path = "./sysroot_src/library/rustc-std-workspace-alloc" }
-rustc-std-workspace-std = { path = "./sysroot_src/library/rustc-std-workspace-std" }
-compiler_builtins = { path = "./sysroot_src/library/compiler-builtins/compiler-builtins" }
-
-# For compiler-builtins we always use a high number of codegen units.
-# The goal here is to place every single intrinsic into its own object
-# file to avoid symbol clashes with the system libgcc if possible. Note
-# that this number doesn't actually produce this many object files, we
-# just don't create more than this number of object files.
-#
-# It's a bit of a bummer that we have to pass this here, unfortunately.
-# Ideally this would be specified through an env var to Cargo so Cargo
-# knows how many CGUs are for this specific crate, but for now
-# per-crate configuration isn't specifiable in the environment.
-[profile.dev.package.compiler_builtins]
-codegen-units = 10000
-
-[profile.release.package.compiler_builtins]
-codegen-units = 10000
-
-[profile.release]
-debug = "limited"
-#lto = "fat" # TODO(antoyo): re-enable when the failing LTO tests regarding proc-macros are fixed.
diff --git a/compiler/rustc_codegen_gcc/build_system/build_sysroot/lib.rs b/compiler/rustc_codegen_gcc/build_system/build_sysroot/lib.rs
deleted file mode 100644
index 0c9ac1ac8e4bd..0000000000000
--- a/compiler/rustc_codegen_gcc/build_system/build_sysroot/lib.rs
+++ /dev/null
@@ -1 +0,0 @@
-#![no_std]
diff --git a/compiler/rustc_codegen_gcc/build_system/src/build.rs b/compiler/rustc_codegen_gcc/build_system/src/build.rs
index ecc4c1b2fe224..94b40319f4a77 100644
--- a/compiler/rustc_codegen_gcc/build_system/src/build.rs
+++ b/compiler/rustc_codegen_gcc/build_system/src/build.rs
@@ -5,7 +5,7 @@ use std::path::Path;
 
 use crate::config::{Channel, ConfigInfo};
 use crate::utils::{
-    copy_file, create_dir, get_sysroot_dir, run_command, run_command_with_output_and_env, walk_dir,
+    create_dir, get_sysroot_dir, run_command, run_command_with_output_and_env, walk_dir,
 };
 
 #[derive(Default)]
@@ -53,11 +53,11 @@ impl BuildArg {
     }
 }
 
-fn cleanup_sysroot_previous_build(start_dir: &Path) {
+fn cleanup_sysroot_previous_build(library_dir: &Path) {
     // Cleanup for previous run
     // Clean target dir except for build scripts and incremental cache
     let _ = walk_dir(
-        start_dir.join("target"),
+        library_dir.join("target"),
         &mut |dir: &Path| {
             for top in &["debug", "release"] {
                 let _ = fs::remove_dir_all(dir.join(top).join("build"));
@@ -95,31 +95,13 @@ fn cleanup_sysroot_previous_build(start_dir: &Path) {
         &mut |_| Ok(()),
         false,
     );
-
-    let _ = fs::remove_file(start_dir.join("Cargo.lock"));
-    let _ = fs::remove_file(start_dir.join("test_target/Cargo.lock"));
-    let _ = fs::remove_dir_all(start_dir.join("sysroot"));
-}
-
-pub fn create_build_sysroot_content(start_dir: &Path) -> Result<(), String> {
-    if !start_dir.is_dir() {
-        create_dir(start_dir)?;
-    }
-    copy_file("build_system/build_sysroot/Cargo.toml", start_dir.join("Cargo.toml"))?;
-    copy_file("build_system/build_sysroot/Cargo.lock", start_dir.join("Cargo.lock"))?;
-
-    let src_dir = start_dir.join("src");
-    if !src_dir.is_dir() {
-        create_dir(&src_dir)?;
-    }
-    copy_file("build_system/build_sysroot/lib.rs", start_dir.join("src/lib.rs"))
 }
 
 pub fn build_sysroot(env: &HashMap<String, String>, config: &ConfigInfo) -> Result<(), String> {
     let start_dir = get_sysroot_dir();
 
-    cleanup_sysroot_previous_build(&start_dir);
-    create_build_sysroot_content(&start_dir)?;
+    let library_dir = start_dir.join("sysroot_src").join("library");
+    cleanup_sysroot_previous_build(&library_dir);
 
     // Builds libs
     let mut rustflags = env.get("RUSTFLAGS").cloned().unwrap_or_default();
@@ -157,9 +139,13 @@ pub fn build_sysroot(env: &HashMap<String, String>, config: &ConfigInfo) -> Resu
         rustflags.push_str(&cg_rustflags);
     }
 
+    args.push(&"--features");
+    args.push(&"backtrace");
+
     let mut env = env.clone();
     env.insert("RUSTFLAGS".to_string(), rustflags);
-    run_command_with_output_and_env(&args, Some(&start_dir), Some(&env))?;
+    let sysroot_dir = library_dir.join("sysroot");
+    run_command_with_output_and_env(&args, Some(&sysroot_dir), Some(&env))?;
 
     // Copy files to sysroot
     let sysroot_path = start_dir.join(format!("sysroot/lib/rustlib/{}/lib/", config.target_triple));
@@ -169,7 +155,7 @@ pub fn build_sysroot(env: &HashMap<String, String>, config: &ConfigInfo) -> Resu
         run_command(&[&"cp", &"-r", &dir_to_copy, &sysroot_path], None).map(|_| ())
     };
     walk_dir(
-        start_dir.join(format!("target/{}/{}/deps", config.target_triple, channel)),
+        library_dir.join(format!("target/{}/{}/deps", config.target_triple, channel)),
         &mut copier.clone(),
         &mut copier,
         false,
@@ -178,7 +164,7 @@ pub fn build_sysroot(env: &HashMap<String, String>, config: &ConfigInfo) -> Resu
     // Copy the source files to the sysroot (Rust for Linux needs this).
     let sysroot_src_path = start_dir.join("sysroot/lib/rustlib/src/rust");
     create_dir(&sysroot_src_path)?;
-    run_command(&[&"cp", &"-r", &start_dir.join("sysroot_src/library/"), &sysroot_src_path], None)?;
+    run_command(&[&"cp", &"-r", &library_dir, &sysroot_src_path], None)?;
 
     Ok(())
 }
diff --git a/compiler/rustc_codegen_gcc/build_system/src/config.rs b/compiler/rustc_codegen_gcc/build_system/src/config.rs
index 650c030ca5393..a5f802e293a94 100644
--- a/compiler/rustc_codegen_gcc/build_system/src/config.rs
+++ b/compiler/rustc_codegen_gcc/build_system/src/config.rs
@@ -352,11 +352,6 @@ impl ConfigInfo {
             None => return Err("no host found".to_string()),
         };
 
-        if self.target_triple.is_empty()
-            && let Some(overwrite) = env.get("OVERWRITE_TARGET_TRIPLE")
-        {
-            self.target_triple = overwrite.clone();
-        }
         if self.target_triple.is_empty() {
             self.target_triple = self.host_triple.clone();
         }
diff --git a/compiler/rustc_codegen_gcc/build_system/src/utils.rs b/compiler/rustc_codegen_gcc/build_system/src/utils.rs
index d77707d5f17a6..fc948c54b24aa 100644
--- a/compiler/rustc_codegen_gcc/build_system/src/utils.rs
+++ b/compiler/rustc_codegen_gcc/build_system/src/utils.rs
@@ -303,19 +303,6 @@ pub fn create_dir<P: AsRef<Path>>(path: P) -> Result<(), String> {
     })
 }
 
-pub fn copy_file<F: AsRef<Path>, T: AsRef<Path>>(from: F, to: T) -> Result<(), String> {
-    fs::copy(&from, &to)
-        .map_err(|error| {
-            format!(
-                "Failed to copy file `{}` into `{}`: {:?}",
-                from.as_ref().display(),
-                to.as_ref().display(),
-                error
-            )
-        })
-        .map(|_| ())
-}
-
 /// This function differs from `git_clone` in how it handles *where* the repository will be cloned.
 /// In `git_clone`, it is cloned in the provided path. In this function, the path you provide is
 /// the parent folder. So if you pass "a" as folder and try to clone "b.git", it will be cloned into
diff --git a/compiler/rustc_codegen_gcc/doc/tips.md b/compiler/rustc_codegen_gcc/doc/tips.md
index 86c22db186e01..e62c3402a292d 100644
--- a/compiler/rustc_codegen_gcc/doc/tips.md
+++ b/compiler/rustc_codegen_gcc/doc/tips.md
@@ -62,14 +62,14 @@ generate it in [gimple.md](./doc/gimple.md).
 
  * Run `./y.sh prepare --cross` so that the sysroot is patched for the cross-compiling case.
  * Set the path to the cross-compiling libgccjit in `gcc-path` (in `config.toml`).
- * Make sure you have the linker for your target (for instance `m68k-unknown-linux-gnu-gcc`) in your `$PATH`. Currently, the linker name is hardcoded as being `$TARGET-gcc`. Specify the target when building the sysroot: `./y.sh build --sysroot --target-triple m68k-unknown-linux-gnu`.
- * Build your project by specifying the target: `OVERWRITE_TARGET_TRIPLE=m68k-unknown-linux-gnu ../y.sh cargo build --target m68k-unknown-linux-gnu`.
+ * Make sure you have the linker for your target (for instance `m68k-unknown-linux-gnu-gcc`) in your `$PATH`. You can specify which linker to use via `CG_RUSTFLAGS="-Clinker=<linker>"`, for instance: `CG_RUSTFLAGS="-Clinker=m68k-unknown-linux-gnu-gcc"`. Specify the target when building the sysroot: `./y.sh build --sysroot --target-triple m68k-unknown-linux-gnu`.
+ * Build your project by specifying the target and the linker to use: `CG_RUSTFLAGS="-Clinker=m68k-unknown-linux-gnu-gcc" ../y.sh cargo build --target m68k-unknown-linux-gnu`.
 
 If the target is not yet supported by the Rust compiler, create a [target specification file](https://docs.rust-embedded.org/embedonomicon/custom-target.html) (note that the `arch` specified in this file must be supported by the rust compiler).
 Then, you can use it the following way:
 
  * Add the target specification file using `--target` as an **absolute** path to build the sysroot: `./y.sh build --sysroot --target-triple m68k-unknown-linux-gnu --target $(pwd)/m68k-unknown-linux-gnu.json`
- * Build your project by specifying the target specification file: `OVERWRITE_TARGET_TRIPLE=m68k-unknown-linux-gnu ../y.sh cargo build --target path/to/m68k-unknown-linux-gnu.json`.
+ * Build your project by specifying the target specification file: `../y.sh cargo build --target path/to/m68k-unknown-linux-gnu.json`.
 
 If you get the following error:
 
diff --git a/compiler/rustc_codegen_gcc/example/mini_core_hello_world.rs b/compiler/rustc_codegen_gcc/example/mini_core_hello_world.rs
index 6b6f71edaf8c9..85489f850e248 100644
--- a/compiler/rustc_codegen_gcc/example/mini_core_hello_world.rs
+++ b/compiler/rustc_codegen_gcc/example/mini_core_hello_world.rs
@@ -6,7 +6,7 @@
 )]
 #![no_core]
 #![allow(dead_code, internal_features, non_camel_case_types)]
-#![rustfmt::skip]
+#![rustfmt_skip]
 
 extern crate mini_core;
 
@@ -198,10 +198,17 @@ fn main() {
         assert_eq!(intrinsics::align_of::<u16>() as u8, 2);
         assert_eq!(intrinsics::align_of_val(&a) as u8, intrinsics::align_of::<&str>() as u8);
 
-        assert!(!const { intrinsics::needs_drop::<u8>() });
-        assert!(!const { intrinsics::needs_drop::<[u8]>() });
-        assert!(const { intrinsics::needs_drop::<NoisyDrop>() });
-        assert!(const { intrinsics::needs_drop::<NoisyDropUnsized>() });
+        /*
+         * TODO: re-enable in the next sync.
+        let u8_needs_drop = const { intrinsics::needs_drop::<u8>() };
+        assert!(!u8_needs_drop);
+        let slice_needs_drop = const { intrinsics::needs_drop::<[u8]>() };
+        assert!(!slice_needs_drop);
+        let noisy_drop = const { intrinsics::needs_drop::<NoisyDrop>() };
+        assert!(noisy_drop);
+        let noisy_unsized_drop = const { intrinsics::needs_drop::<NoisyDropUnsized>() };
+        assert!(noisy_unsized_drop);
+        */
 
         Unique {
             pointer: 0 as *const &str,
diff --git a/compiler/rustc_codegen_gcc/rust-toolchain b/compiler/rustc_codegen_gcc/rust-toolchain
index bccbc6cd2c5cd..2fe8ec4647fad 100644
--- a/compiler/rustc_codegen_gcc/rust-toolchain
+++ b/compiler/rustc_codegen_gcc/rust-toolchain
@@ -1,3 +1,3 @@
 [toolchain]
-channel = "nightly-2025-06-28"
+channel = "nightly-2025-07-04"
 components = ["rust-src", "rustc-dev", "llvm-tools-preview"]
diff --git a/compiler/rustc_codegen_gcc/src/builder.rs b/compiler/rustc_codegen_gcc/src/builder.rs
index 28d1ec7d89564..a4ec4bf8deac4 100644
--- a/compiler/rustc_codegen_gcc/src/builder.rs
+++ b/compiler/rustc_codegen_gcc/src/builder.rs
@@ -971,7 +971,11 @@ impl<'a, 'gcc, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'gcc, 'tcx> {
 
     fn volatile_load(&mut self, ty: Type<'gcc>, ptr: RValue<'gcc>) -> RValue<'gcc> {
         let ptr = self.context.new_cast(self.location, ptr, ty.make_volatile().make_pointer());
-        ptr.dereference(self.location).to_rvalue()
+        // (FractalFir): We insert a local here, to ensure this volatile load can't move across
+        // blocks.
+        let local = self.current_func().new_local(self.location, ty, "volatile_tmp");
+        self.block.add_assignment(self.location, local, ptr.dereference(self.location).to_rvalue());
+        local.to_rvalue()
     }
 
     fn atomic_load(
diff --git a/compiler/rustc_codegen_gcc/src/lib.rs b/compiler/rustc_codegen_gcc/src/lib.rs
index d81bcc5977563..af416929ea73d 100644
--- a/compiler/rustc_codegen_gcc/src/lib.rs
+++ b/compiler/rustc_codegen_gcc/src/lib.rs
@@ -273,6 +273,10 @@ fn new_context<'gcc, 'tcx>(tcx: TyCtxt<'tcx>) -> Context<'gcc> {
 }
 
 impl ExtraBackendMethods for GccCodegenBackend {
+    fn supports_parallel(&self) -> bool {
+        false
+    }
+
     fn codegen_allocator(
         &self,
         tcx: TyCtxt<'_>,
@@ -341,8 +345,7 @@ impl Deref for SyncContext {
 }
 
 unsafe impl Send for SyncContext {}
-// FIXME(antoyo): that shouldn't be Sync. Parallel compilation is currently disabled with "-Zno-parallel-llvm".
-// TODO: disable it here by returning false in CodegenBackend::supports_parallel().
+// FIXME(antoyo): that shouldn't be Sync. Parallel compilation is currently disabled with "CodegenBackend::supports_parallel()".
 unsafe impl Sync for SyncContext {}
 
 impl WriteBackendMethods for GccCodegenBackend {
diff --git a/compiler/rustc_codegen_gcc/src/mono_item.rs b/compiler/rustc_codegen_gcc/src/mono_item.rs
index 51f35cbdee472..ff188c437daea 100644
--- a/compiler/rustc_codegen_gcc/src/mono_item.rs
+++ b/compiler/rustc_codegen_gcc/src/mono_item.rs
@@ -64,7 +64,7 @@ impl<'gcc, 'tcx> PreDefineCodegenMethods<'tcx> for CodegenCx<'gcc, 'tcx> {
         if linkage != Linkage::Internal && self.tcx.is_compiler_builtins(LOCAL_CRATE) {
             #[cfg(feature = "master")]
             decl.add_attribute(FnAttribute::Visibility(gccjit::Visibility::Hidden));
-        } else {
+        } else if visibility != Visibility::Default {
             #[cfg(feature = "master")]
             decl.add_attribute(FnAttribute::Visibility(base::visibility_to_gcc(visibility)));
         }
diff --git a/compiler/rustc_codegen_gcc/tests/failing-ui-tests.txt b/compiler/rustc_codegen_gcc/tests/failing-ui-tests.txt
index 544d0bfc71050..6979c04d53430 100644
--- a/compiler/rustc_codegen_gcc/tests/failing-ui-tests.txt
+++ b/compiler/rustc_codegen_gcc/tests/failing-ui-tests.txt
@@ -80,3 +80,5 @@ tests/ui/uninhabited/uninhabited-transparent-return-abi.rs
 tests/ui/coroutine/panic-drops-resume.rs
 tests/ui/coroutine/panic-drops.rs
 tests/ui/coroutine/panic-safe.rs
+tests/ui/process/nofile-limit.rs
+tests/ui/simd/intrinsic/generic-arithmetic-pass.rs
diff --git a/compiler/rustc_codegen_gcc/tests/run/asm.rs b/compiler/rustc_codegen_gcc/tests/run/asm.rs
index 2dbf43be664dc..9b15a28d82988 100644
--- a/compiler/rustc_codegen_gcc/tests/run/asm.rs
+++ b/compiler/rustc_codegen_gcc/tests/run/asm.rs
@@ -16,6 +16,7 @@ add_asm:
      ret"
 );
 
+#[cfg(target_arch = "x86_64")]
 extern "C" {
     fn add_asm(a: i64, b: i64) -> i64;
 }
diff --git a/compiler/rustc_codegen_gcc/tests/run/float.rs b/compiler/rustc_codegen_gcc/tests/run/float.rs
index 424fa1cf4ad53..df555f383fe08 100644
--- a/compiler/rustc_codegen_gcc/tests/run/float.rs
+++ b/compiler/rustc_codegen_gcc/tests/run/float.rs
@@ -3,8 +3,6 @@
 // Run-time:
 //   status: 0
 
-#![feature(const_black_box)]
-
 fn main() {
     use std::hint::black_box;
 
@@ -15,14 +13,14 @@ fn main() {
         }};
     }
 
-    check!(i32, (black_box(0.0f32) as i32));
+    check!(i32, black_box(0.0f32) as i32);
 
-    check!(u64, (black_box(f32::NAN) as u64));
-    check!(u128, (black_box(f32::NAN) as u128));
+    check!(u64, black_box(f32::NAN) as u64);
+    check!(u128, black_box(f32::NAN) as u128);
 
-    check!(i64, (black_box(f64::NAN) as i64));
-    check!(u64, (black_box(f64::NAN) as u64));
+    check!(i64, black_box(f64::NAN) as i64);
+    check!(u64, black_box(f64::NAN) as u64);
 
-    check!(i16, (black_box(f32::MIN) as i16));
-    check!(i16, (black_box(f32::MAX) as i16));
+    check!(i16, black_box(f32::MIN) as i16);
+    check!(i16, black_box(f32::MAX) as i16);
 }
diff --git a/compiler/rustc_codegen_gcc/tests/run/int.rs b/compiler/rustc_codegen_gcc/tests/run/int.rs
index 47b5dea46f8de..e20ecc23679d6 100644
--- a/compiler/rustc_codegen_gcc/tests/run/int.rs
+++ b/compiler/rustc_codegen_gcc/tests/run/int.rs
@@ -3,8 +3,6 @@
 // Run-time:
 //   status: 0
 
-#![feature(const_black_box)]
-
 fn main() {
     use std::hint::black_box;
 
diff --git a/compiler/rustc_codegen_gcc/tests/run/volatile.rs b/compiler/rustc_codegen_gcc/tests/run/volatile.rs
index 8b0433125936b..94a7bdc5c0668 100644
--- a/compiler/rustc_codegen_gcc/tests/run/volatile.rs
+++ b/compiler/rustc_codegen_gcc/tests/run/volatile.rs
@@ -5,13 +5,14 @@
 
 use std::mem::MaybeUninit;
 
+#[allow(dead_code)]
 #[derive(Debug)]
 struct Struct {
     pointer: *const (),
     func: unsafe fn(*const ()),
 }
 
-fn func(ptr: *const ()) {
+fn func(_ptr: *const ()) {
 }
 
 fn main() {
diff --git a/compiler/rustc_codegen_gcc/tests/run/volatile2.rs b/compiler/rustc_codegen_gcc/tests/run/volatile2.rs
index a177b817ab35a..bdcb82598789c 100644
--- a/compiler/rustc_codegen_gcc/tests/run/volatile2.rs
+++ b/compiler/rustc_codegen_gcc/tests/run/volatile2.rs
@@ -6,8 +6,6 @@
 mod libc {
     #[link(name = "c")]
     extern "C" {
-        pub fn puts(s: *const u8) -> i32;
-
         pub fn sigaction(signum: i32, act: *const sigaction, oldact: *mut sigaction) -> i32;
         pub fn mmap(addr: *mut (), len: usize, prot: i32, flags: i32, fd: i32, offset: i64) -> *mut ();
         pub fn mprotect(addr: *mut (), len: usize, prot: i32) -> i32;
@@ -61,7 +59,7 @@ fn main() {
             panic!("error: mmap failed");
         }
 
-        let p_count = (&mut COUNT) as *mut u32;
+        let p_count = (&raw mut COUNT) as *mut u32;
         p_count.write_volatile(0);
 
         // Trigger segfaults
@@ -94,7 +92,7 @@ fn main() {
 }
 
 unsafe extern "C" fn segv_handler(_: i32, _: *mut (), _: *mut ()) {
-    let p_count = (&mut COUNT) as *mut u32;
+    let p_count = (&raw mut COUNT) as *mut u32;
     p_count.write_volatile(p_count.read_volatile() + 1);
     let count = p_count.read_volatile();