From e6cf37a857aa0e239833da0bd97745b0a4f5629f Mon Sep 17 00:00:00 2001
From: Daniel Leung <daniel.leung@intel.com>
Date: Thu, 19 Dec 2019 16:22:00 -0800
Subject: [PATCH] cmake: ld: use linker prefix for undefined symbols

The undefined symbol option "-u" applies to linker so prefix
it with the linker prefix (usually "-Wl"). This fixes warnings
from LLVM/Clang about unknown arguments.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>
---
 cmake/linker/ld/target.cmake | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cmake/linker/ld/target.cmake b/cmake/linker/ld/target.cmake
index 9523f429854..8fd66a23493 100644
--- a/cmake/linker/ld/target.cmake
+++ b/cmake/linker/ld/target.cmake
@@ -57,7 +57,7 @@ endmacro()
 # Force symbols to be entered in the output file as undefined symbols
 function(toolchain_ld_force_undefined_symbols)
   foreach(symbol ${ARGN})
-    zephyr_link_libraries(-u${symbol})
+    zephyr_link_libraries(${LINKERFLAGPREFIX},-u,${symbol})
   endforeach()
 endfunction()