Add wasm bindings for Pubkey and Keypair

sdk/macro/src/lib.rs

@@ -373,3 +373,31 @@ pub fn pubkeys(input: TokenStream) -> TokenStream {
     let pubkeys = parse_macro_input!(input as Pubkeys);
     TokenStream::from(quote! {#pubkeys})
 }
+
+// The normal `wasm_bindgen` macro generates a .bss section which causes the resulting
+// BPF program to fail to load, so for now this stub should be used when building for BPF
+#[proc_macro_attribute]
+pub fn wasm_bindgen_stub(_attr: TokenStream, item: TokenStream) -> TokenStream {
+    match parse_macro_input!(item as syn::Item) {
+        syn::Item::Struct(mut item_struct) => {
+            if let syn::Fields::Named(fields) = &mut item_struct.fields {
+                // Strip out any `#[wasm_bindgen]` added to struct fields. This is custom
+                // syntax supplied by the normal `wasm_bindgen` macro.
+                for field in fields.named.iter_mut() {
+                    field.attrs.retain(|attr| {
+                        !attr
+                            .path
+                            .segments
+                            .iter()
+                            .any(|segment| segment.ident == "wasm_bindgen")
+                    });
+                }
+            }
+            quote! { #item_struct }
+        }
+        item => {
+            quote!(#item)
+        }
+    }
+    .into()
+}