diff --git a/src/builder.rs b/src/builder.rs
index 6253816d37d..d353704fb75 100644
--- a/src/builder.rs
+++ b/src/builder.rs
@@ -31,7 +31,7 @@
 use rustc_target::abi::{
     self, call::FnAbi, Align, HasDataLayout, Size, TargetDataLayout, WrappingRange,
 };
-use rustc_target::spec::{HasTargetSpec, Target};
+use rustc_target::spec::{HasTargetSpec, HasWasmCAbiOpt, Target, WasmCAbi};
 
 use crate::common::{type_is_pointer, SignType, TypeReflection};
 use crate::context::CodegenCx;
@@ -2352,6 +2352,12 @@ fn target_spec(&self) -> &Target {
     }
 }
 
+impl<'tcx> HasWasmCAbiOpt for Builder<'_, '_, 'tcx> {
+    fn wasm_c_abi_opt(&self) -> WasmCAbi {
+        self.cx.wasm_c_abi_opt()
+    }
+}
+
 pub trait ToGccComp {
     fn to_gcc_comparison(&self) -> ComparisonOp;
 }
diff --git a/src/context.rs b/src/context.rs
index 9e6cf3e34df..16a85b4e8fa 100644
--- a/src/context.rs
+++ b/src/context.rs
@@ -20,7 +20,7 @@
 use rustc_target::abi::{
     call::FnAbi, HasDataLayout, PointeeInfo, Size, TargetDataLayout, VariantIdx,
 };
-use rustc_target::spec::{HasTargetSpec, Target, TlsModel};
+use rustc_target::spec::{HasTargetSpec, HasWasmCAbiOpt, Target, TlsModel, WasmCAbi};
 
 use crate::callee::get_fn;
 use crate::common::SignType;
@@ -557,6 +557,12 @@ fn target_spec(&self) -> &Target {
     }
 }
 
+impl<'gcc, 'tcx> HasWasmCAbiOpt for CodegenCx<'gcc, 'tcx> {
+    fn wasm_c_abi_opt(&self) -> WasmCAbi {
+        self.tcx.sess.opts.unstable_opts.wasm_c_abi
+    }
+}
+
 impl<'gcc, 'tcx> LayoutOfHelpers<'tcx> for CodegenCx<'gcc, 'tcx> {
     type LayoutOfResult = TyAndLayout<'tcx>;