Propagate linker flags from the command line
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5ae4569..918b2fc 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -46,7 +46,7 @@
 
 if(APPLE)
 elseif(UNIX)
-  set(CMAKE_EXE_LINKER_FLAGS "-Wl,--build-id")
+  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--build-id")
 endif()
 
 # When using Ninja, compiler output won't be colorized without this.