Try using the library path to define the rpath

This seems to be working, although it's not great that the library is in
a weird SDK path...

Author: llvm-beanz

tools/api-query/CMakeLists.txt

@@ -4,6 +4,7 @@ add_offloadtest_tool(api-query
 target_link_libraries(api-query PRIVATE LLVMSupport OffloadTestAPI)
 
 if (APPLE AND OFFLOADTEST_ENABLE_VULKAN)
+  get_filename_component(_Vulkan_LIB_DIR ${Vulkan_LIBRARY} DIRECTORY)
   set_property(TARGET api-query APPEND_STRING PROPERTY
-               LINK_FLAGS " -Wl,-rpath,/usr/local/lib ")
+               LINK_FLAGS " -Wl,-rpath,${_Vulkan_LIB_DIR} ")
 endif()

tools/offloader/CMakeLists.txt

@@ -8,6 +8,7 @@ target_link_libraries(offloader PRIVATE
                       OffloadTestSupport)
 
 if (APPLE AND OFFLOADTEST_ENABLE_VULKAN)
+  get_filename_component(_Vulkan_LIB_DIR ${Vulkan_LIBRARY} DIRECTORY)
   set_property(TARGET offloader APPEND_STRING PROPERTY
-               LINK_FLAGS " -Wl,-rpath,/usr/local/lib ")
+               LINK_FLAGS " -Wl,-rpath,${_Vulkan_LIB_DIR} ")
 endif()