diff --git a/src/codegen/llvm.zig b/src/codegen/llvm.zig
index 0c6aaa66fb..0bbc3aee46 100644
--- a/src/codegen/llvm.zig
+++ b/src/codegen/llvm.zig
@@ -1341,7 +1341,7 @@ pub const Object = struct {
                                 try attributes.addParamAttr(llvm_arg_i, .@"noalias", &o.builder);
                             }
                         }
-                        if (param_ty.zigTypeTag(zcu) != .optional) {
+                        if (param_ty.zigTypeTag(zcu) != .optional and !ptr_info.flags.is_allowzero) {
                             try attributes.addParamAttr(llvm_arg_i, .nonnull, &o.builder);
                         }
                         if (ptr_info.flags.is_const) {
@@ -5410,7 +5410,7 @@ pub const FuncGen = struct {
                             try attributes.addParamAttr(llvm_arg_i, .@"noalias", &o.builder);
                         }
                     }
-                    if (param_ty.zigTypeTag(zcu) != .optional) {
+                    if (param_ty.zigTypeTag(zcu) != .optional and !ptr_info.flags.is_allowzero) {
                         try attributes.addParamAttr(llvm_arg_i, .nonnull, &o.builder);
                     }
                     if (ptr_info.flags.is_const) {