From 667e17a4212f491b41096c1b193bef06723591e3 Mon Sep 17 00:00:00 2001
From: Riley Dulin <dulinr@meta.com>
Date: Mon, 24 Nov 2025 11:04:31 -0800
Subject: [PATCH] Add conda lib to static linker search path for builds (#1972)

Summary:

Our install instructions say to use `conda install libunwind`, but the rust compiler
is unable to locate it.
Add a `-L` flag when building from within python to add the conda environment libraries.
This should help rust locate the libraries it needs.

Reviewed By: colin2328

Differential Revision: D87665225
---
 setup.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/setup.py b/setup.py
index c1e0fb38d..1f1ec13d3 100644
--- a/setup.py
+++ b/setup.py
@@ -154,6 +154,10 @@ def run(self):
         "link-arg=-Wl,-rpath,$ORIGIN/../../..",
         "-C",
         "link-arg=-Wl,-rpath," + conda_lib,
+        # Add the conda lib to the search path for the linker, as libraries like
+        # libunwind may be installed there.
+        "-L",
+        conda_lib,
     ]
     if py_lib:
         flags += ["-C", "link-arg=-Wl,-rpath," + py_lib]