diff --git a/src/codegen.cpp b/src/codegen.cpp
index d54d06f3b..9085d4ea7 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -2280,6 +2280,9 @@ void walk_function_params(CodeGen *g, ZigType *fn_type, FnWalk *fn_walk) {
                 if ((param_type->id == ZigTypeIdPointer && param_type->data.pointer.is_const) || is_byval) {
                     addLLVMArgAttr(llvm_fn, (unsigned)gen_index, "readonly");
                 }
+                if (get_codegen_ptr_type(param_type) != nullptr) {
+                    addLLVMArgAttrInt(llvm_fn, (unsigned)gen_index, "align", get_ptr_align(g, param_type));
+                }
                 if (type_is_nonnull_ptr(param_type)) {
                     addLLVMArgAttr(llvm_fn, (unsigned)gen_index, "nonnull");
                 }