Fix llvm 8 build

cmake/unix.cmake

@@ -21,7 +21,7 @@ elseif (${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD" OR ${CMAKE_SYSTEM_NAME} MATCHES "
   find_library(FS_LIB NAMES c++experimental)
   set(LIBTUNTAP_IMPL ${TT_ROOT}/tuntap-unix-freebsd.c ${TT_ROOT}/tuntap-unix-bsd.c)
 elseif (${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
-  find_library(FS_LIB NAMES stdc++fs c++experimental stdc++fs)
+  find_library(FS_LIB NAMES c++fs c++experimental stdc++fs)
 
   if(FS_LIB STREQUAL FS_LIB-NOTFOUND)
     add_subdirectory(vendor)

llarp/CMakeLists.txt

@@ -53,7 +53,7 @@ set(LIB_UTIL_SRC
 
 add_library(${UTIL_LIB} STATIC ${LIB_UTIL_SRC})
 target_include_directories(${UTIL_LIB} PUBLIC ${CMAKE_CURRENT_SOURCE_DIR} ${PROJECT_SOURCE_DIR}/include)
-target_link_libraries(${UTIL_LIB} PUBLIC ${CRYPTOGRAPHY_LIB})
+target_link_libraries(${UTIL_LIB} PUBLIC ${CRYPTOGRAPHY_LIB} ${FS_LIB})
 target_link_libraries_system(${UTIL_LIB} absl::synchronization absl::hash absl::container nlohmann_json::nlohmann_json)
 
 # cut back on fluff
@@ -242,7 +242,7 @@ endif()
 
 add_library(${STATIC_LIB} STATIC ${LIB_SRC})
 set(LIBS ${LIBS} libutp)
-target_link_libraries(${STATIC_LIB} PUBLIC cxxopts ${ABYSS_LIB} ${PLATFORM_LIB} ${UTIL_LIB} ${CRYPTOGRAPHY_LIB})
+target_link_libraries(${STATIC_LIB} PUBLIC cxxopts ${ABYSS_LIB} ${PLATFORM_LIB} ${UTIL_LIB} ${CRYPTOGRAPHY_LIB} ${FS_LIB})
 
 if(${CMAKE_SYSTEM_NAME} MATCHES "FreeBSD")
   target_include_directories(${PLATFORM_LIB} SYSTEM PUBLIC /usr/local/include)