Don't warn about `v128` in wasm ABI transition

This has other warnings if necessary and doesn't need extra warnings
from this FCW.

cc #138762

1 files changed, 6 insertions, 0 deletions

diff --git a/compiler/rustc_monomorphize/src/mono_checks/abi_check.rs b/compiler/rustc_monomorphize/src/mono_checks/abi_check.rs
index 94ee34c8b7b..81bf8c5d21c 100644
--- a/compiler/rustc_monomorphize/src/mono_checks/abi_check.rs
+++ b/compiler/rustc_monomorphize/src/mono_checks/abi_check.rs
@@ -99,6 +99,12 @@ fn wasm_abi_safe<'tcx>(tcx: TyCtxt<'tcx>, arg: &ArgAbi<'tcx, Ty<'tcx>>) -> bool
         return true;
     }
 
+    // Both the old and the new ABIs treat vector types like `v128` the same
+    // way.
+    if uses_vector_registers(&arg.mode, &arg.layout.backend_repr) {
+        return true;
+    }
+
     // This matches `unwrap_trivial_aggregate` in the wasm ABI logic.
     if arg.layout.is_aggregate() {
         let cx = LayoutCx::new(tcx, TypingEnv::fully_monomorphized());