1 files changed, 3 insertions, 22 deletions
diff --git a/compiler/rustc_target/src/callconv/mod.rs b/compiler/rustc_target/src/callconv/mod.rs
index 50ac6c8fcde..b49dd258869 100644
--- a/compiler/rustc_target/src/callconv/mod.rs
+++ b/compiler/rustc_target/src/callconv/mod.rs
@@ -6,7 +6,6 @@ use rustc_abi::{
     Size, TyAbiInterface, TyAndLayout,
 };
 use rustc_macros::HashStable_Generic;
-use rustc_span::Symbol;
 
 use crate::spec::{HasTargetSpec, HasWasmCAbiOpt, HasX86AbiOpt, WasmCAbi};
 
@@ -623,19 +622,8 @@ impl<'a, Ty: fmt::Display> fmt::Debug for FnAbi<'a, Ty> {
     }
 }
 
-/// Error produced by attempting to adjust a `FnAbi`, for a "foreign" ABI.
-#[derive(Copy, Clone, Debug, HashStable_Generic)]
-pub enum AdjustForForeignAbiError {
-    /// Target architecture doesn't support "foreign" (i.e. non-Rust) ABIs.
-    Unsupported { arch: Symbol, abi: ExternAbi },
-}
-
 impl<'a, Ty> FnAbi<'a, Ty> {
-    pub fn adjust_for_foreign_abi<C>(
-        &mut self,
-        cx: &C,
-        abi: ExternAbi,
-    ) -> Result<(), AdjustForForeignAbiError>
+    pub fn adjust_for_foreign_abi<C>(&mut self, cx: &C, abi: ExternAbi)
     where
         Ty: TyAbiInterface<'a, C> + Copy,
         C: HasDataLayout + HasTargetSpec + HasWasmCAbiOpt + HasX86AbiOpt,
@@ -644,7 +632,7 @@ impl<'a, Ty> FnAbi<'a, Ty> {
             if let Some(arg) = self.args.first_mut() {
                 arg.pass_by_stack_offset(None);
             }
-            return Ok(());
+            return;
         }
 
         let spec = cx.target_spec();
@@ -719,15 +707,8 @@ impl<'a, Ty> FnAbi<'a, Ty> {
             }
             "wasm64" => wasm::compute_c_abi_info(cx, self),
             "bpf" => bpf::compute_abi_info(self),
-            arch => {
-                return Err(AdjustForForeignAbiError::Unsupported {
-                    arch: Symbol::intern(arch),
-                    abi,
-                });
-            }
+            arch => panic!("no lowering implemented for {arch}"),
         }
-
-        Ok(())
     }
 
     pub fn adjust_for_rust_abi<C>(&mut self, cx: &C, abi: ExternAbi)