--- souper-1be75fe6a96993b57dcba038798fe6d1c7d113eb-src/CMakeLists.txt.orig     2017-01-20 13:55:14.783632588 -0600
+++ souper-1be75fe6a96993b57dcba038798fe6d1c7d113eb-src/CMakeLists.txt  2017-01-20 13:55:20.505728456 -0600
@@ -33,7 +33,10 @@
   OUTPUT_VARIABLE LLVM_SYSTEM_LIBS
   OUTPUT_STRIP_TRAILING_WHITESPACE
 )
-set(LLVM_LIBS "${LLVM_LIBS} ${LLVM_SYSTEM_LIBS}")
+
+if (LLVM_SYSTEM_LIBS)
+  set(LLVM_LIBS "${LLVM_LIBS} ${LLVM_SYSTEM_LIBS}")
+endif()

 execute_process(
   COMMAND ${LLVM_CONFIG_EXECUTABLE} --ldflags