[Bug c/69981] -f[no]keep-static-consts has no effect

[equinox-gccbugs at diac24 dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69981

--- Comment #6 from David L. <equinox-gccbugs at diac24 dot net> ---
Created attachment 37808
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=37808&action=edit
patch (gcc-5.3.0)

patch attached (probably makes the user's PC explode and burns down their
house)

varpool_node::finalize_decl (tree decl)
-    node->force_output = true;
+    node->force_output = !TREE_READONLY (decl) || flag_keep_static_consts;