This patch tightens the conditions on when assemble_external() may be
called. It also removes a comment that "most platforms do not define
ASM_OUTPUT_EXTERNAL", because hasn't been true since r119764 added a
definition of ASM_OUTPUT_EXTERNAL to elfos.h.
This is the first step toward addressing PR17982 on the trunk for GCC
4.8. The next step is to change pending_assemble_externals to
pending_assemble_visibility, and fold assemble_external_real() back
But first, this patch. I don't think this is very risky, because GCC
now always works in unit-at-a-time mode. But I think it would be good
to have this on the trunk for a week or so before proceeding.
Bootstrapped & tested on x86_64-unknown-linux-gnu. OK for trunk?
* varasm.c (assemble_external): Assert this function is only called
during or after expanding to RTL.
--- varasm.c (revision 185762)
+++ varasm.c (working copy)
@@ -2166,12 +2166,18 @@ static GTY(()) tree weak_decls;
assemble_external (tree decl ATTRIBUTE_UNUSED)
- /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
- main body of this code is only rarely exercised. To provide some
- testing, on all platforms, we make sure that the ASM_OUT_FILE is
- open. If it's not, we should not be calling this function. */
+ /* Make sure that the ASM_OUT_FILE is open.
+ If it's not, we should not be calling this function. */
+ /* This function should only be called if we are expanding, or have
+ expanded, to RTL.
+ Ideally, only final.c would be calling this function, but it is
+ not clear whether that would break things somehow. See PR 17982
+ for further discussion. */
+ gcc_assert (cgraph_state == CGRAPH_STATE_EXPANSION
+ || cgraph_state == CGRAPH_STATE_FINISHED);
if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))