build: prefer lld over gold

lld is the LLVM linker which is faster than gold.  Prefer lld over gold
(that is, if `-DUSE_LLD_LINKER` is provided, gold will not be used).

Author: compnerd

CMakeLists.txt

@@ -91,17 +91,18 @@ option(BUILD_SHARED_LIBS "build shared libraries" ON)
 
 option(ENABLE_TESTING "build libdispatch tests" ON)
 
+option(USE_LLD_LINKER "use the lld linker" OFF)
+
 if(CMAKE_SYSTEM_NAME STREQUAL Linux OR
    CMAKE_SYSTEM_NAME STREQUAL FreeBSD OR
-   CMAKE_SYSTEM_NAME STREQUAL Android)
+   CMAKE_SYSTEM_NAME STREQUAL Android AND
+   NOT USE_LLD_LINKER)
   set(USE_GOLD_LINKER_DEFAULT ON)
 else()
   set(USE_GOLD_LINKER_DEFAULT OFF)
 endif()
 option(USE_GOLD_LINKER "use the gold linker" ${USE_GOLD_LINKER_DEFAULT})
 
-option(USE_LLD_LINKER "use the lld linker" OFF)
-
 option(ENABLE_THREAD_LOCAL_STORAGE "enable usage of thread local storage via _Thread_local" ON)
 set(DISPATCH_USE_THREAD_LOCAL_STORAGE ${ENABLE_THREAD_LOCAL_STORAGE})