rejuvenate the comments in the temporary glibc_dir field

src/python/pants/backend/native/subsystems/native_toolchain.py

@@ -90,7 +90,10 @@ def subsystem_dependencies(cls):
 
   @memoized_method
   def glibc_dir(self):
-    # FIXME: this can be removed once #5815 lands (GCC should be made to depend on GLibc on Linux).
+    # FIXME: Once #5815 lands, the "compiler" datatype should be given a field for
+    # (DY)?LD_LIBRARY_PATH entries. GCC and LLVM should be made to depend on GLibc on Linux and
+    # provide glibc in the new library path field. This provides necessary files including crti.o
+    # that are not included in the compiler.
     normalized_os_name = get_normalized_os_name()
     if normalized_os_name == 'darwin':
       return None