From 7f5955a081e2f8db5bcea4bde47c0cbd5ff3ac16 Mon Sep 17 00:00:00 2001
From: George Stagg <george.stagg@posit.co>
Date: Wed, 13 Dec 2023 10:11:26 +0000
Subject: [PATCH] Ensure library link flags are unique

Fixes compiling with Emscripten for webR, where linking is static and
so multiple instances of the same library link flag, such as `-lz`,
leads to duplicate symbol errors.
---
 configure | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/configure b/configure
index 6f7b8f96..1a8f7a9b 100755
--- a/configure
+++ b/configure
@@ -49,6 +49,9 @@ elif [ `uname` = "Darwin" ]; then
   fi
 fi
 
+# Ensure that lib link flags are unique
+PKG_LIBS=$(echo ${PKG_LIBS} | xargs -n1 | sort -u | xargs)
+
 # For debugging
 echo "Using PKG_CFLAGS=$PKG_CFLAGS"
 echo "Using PKG_LIBS=$PKG_LIBS"