From bea4c895c1f312561221f6a0319bd76400c821f4 Mon Sep 17 00:00:00 2001
From: Alex Nails <alex.nails@radixark.ai>
Date: Mon, 20 Apr 2026 02:20:14 -0700
Subject: [PATCH] [gRPC] Pass --experimental_allow_proto3_optional to protoc in
 build.rs (#23226)

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
---
 rust/sglang-grpc/build.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/rust/sglang-grpc/build.rs b/rust/sglang-grpc/build.rs
index 8ecaeaa55..5ee1bb2d5 100644
--- a/rust/sglang-grpc/build.rs
+++ b/rust/sglang-grpc/build.rs
@@ -4,6 +4,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     tonic_build::configure()
         .build_server(true)
         .build_client(false)
+        .protoc_arg("--experimental_allow_proto3_optional")
         .file_descriptor_set_path(
             std::path::PathBuf::from(std::env::var("OUT_DIR").unwrap())
                 .join("sglang_descriptor.bin"),