SYMBOL_REF_FLAG

[Phil Blundell]

The ARM backend has some kind of support for referencing static globals
in PIC code using (GOTOFF) relocs rather than (GOT).  In practice though
this is never triggering because it lacks enough information to do
anything useful.  Other backends seem to encode the knowledge of whether
a SYMBOL_REF has global linkage using SYMBOL_REF_FLAG (ie rtx->volatil),
but the arm backend is already using this for other purposes.

Are there any other flag bits in SYMBOL_REFs that could be safely
pressed into service for this?

p.