srsran_rf, ASAN: Enforce RPATH instead of RUNPATH to find RF plugins in build tree when built with ASAN.

CMakeLists.txt

@@ -498,8 +498,12 @@ if(CMAKE_C_COMPILER_ID MATCHES "GNU" OR CMAKE_C_COMPILER_ID MATCHES "Clang")
   endif ()
 
   if (ENABLE_ASAN)
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fsanitize=address -fno-omit-frame-pointer")
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=address -fno-omit-frame-pointer")
+    # Note: When using ASAN, we need to ensure the use of RPATH instead of RUNPATH via "-Wl,--disable-new-dtags"
+    # While RPATH is default, some systems (e.g. Ubuntu 18.04 and 20.04) use RUNPATH by default, which is non-transitive.
+    # Since ASAN intercepts dlopen(), by which it replaces the dynamic string token "$ORIGIN" to its own location,
+    # the RF plugins won't be found by "libsrsran_rf.so" when using ASAN + RUNPATH in the top-level executable.
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fsanitize=address -fno-omit-frame-pointer -Wl,--disable-new-dtags")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=address -fno-omit-frame-pointer -Wl,--disable-new-dtags")
   endif (ENABLE_ASAN)
 
   if (ENABLE_TSAN)