From cf9a4575ae74a57496fe2f2a569cc0edd2d044e0 Mon Sep 17 00:00:00 2001
From: Dmitri Makarov <dmakarov@users.noreply.github.com>
Date: Sat, 10 Jul 2021 18:24:26 -0700
Subject: [PATCH] Prevent duplication of RUSTFLAGS settings in cargo-build-bpf
 subprocesses (#18576)

---
 sdk/cargo-build-bpf/src/main.rs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/sdk/cargo-build-bpf/src/main.rs b/sdk/cargo-build-bpf/src/main.rs
index 127f7df070..c831159a8a 100644
--- a/sdk/cargo-build-bpf/src/main.rs
+++ b/sdk/cargo-build-bpf/src/main.rs
@@ -433,7 +433,13 @@ fn build_bpf_package(config: &Config, target_directory: &Path, package: &cargo_m
     env::set_var("OBJDUMP", llvm_bin.join("llvm-objdump"));
     env::set_var("OBJCOPY", llvm_bin.join("llvm-objcopy"));
     let rustflags = match env::var("RUSTFLAGS") {
-        Ok(rf) => rf + &" -C lto=no".to_string(),
+        Ok(rf) => {
+            if rf.contains("-C lto=no") {
+                rf
+            } else {
+                rf + &" -C lto=no".to_string()
+            }
+        }
         _ => "-C lto=no".to_string(),
     };
     if config.verbose {