PR23648, Symbols based on MEMORY regions confuse --gc-sections

[Alan Modra]

Running lang_do_memory_regions earlier seems a reasonable solution to
gaining better values for symbols prior to lang_gc_sections.

PR ld/23648
* ldlang.c (lang_process): Move lang_do_memory_regions earlier.
Comment on lang_do_assignments call.
* ldgram.y (origin_exp): Don't assign region->current.

diff --git a/ld/ldgram.y b/ld/ldgram.y
index cba0486259..81ed85e9a0 100644
--- a/ld/ldgram.y
+++ b/ld/ldgram.y
@@ -819,7 +819,6 @@ origin_spec:
ORIGIN '=' mustbe_exp
{
region->origin_exp = $3;
- region->current = region->origin;
}
;

diff --git a/ld/ldlang.c b/ld/ldlang.c
index d644b56812..1ac5eb1ee2 100644
--- a/ld/ldlang.c
+++ b/ld/ldlang.c
@@ -7180,6 +7180,9 @@ lang_process (void)
current_target = default_target;
lang_statement_iteration++;
open_input_bfds (statement_list.head, OPEN_BFD_NORMAL);
+ /* open_input_bfds also handles assignments, so we can give values
+ to symbolic origin/length now. */
+ lang_do_memory_regions ();

#ifdef ENABLE_PLUGINS
if (link_info.lto_plugin_active)
@@ -7322,8 +7325,6 @@ lang_process (void)
/* PR 13683: We must rerun the assignments prior to running garbage
collection in order to make sure that all symbol aliases are resolved. */
lang_do_assignments (lang_mark_phase_enum);
-
- lang_do_memory_regions();
expld.phase = lang_first_phase_enum;

/* Size up the common data. */
@@ -7408,8 +7409,11 @@ lang_process (void)
/* Fix any __start, __stop, .startof. or .sizeof. symbols. */
lang_finalize_start_stop ();

- /* Do all the assignments, now that we know the final resting places
- of all the symbols. */
+ /* Do all the assignments again, to report errors. Assignment
+ statements are processed multiple times, updating symbols; In
+ open_input_bfds, lang_do_assignments, and lang_size_sections.
+ Since lang_relax_sections calls lang_do_assignments, symbols are
+ also updated in ldemul_after_allocation. */
lang_do_assignments (lang_final_phase_enum);

ldemul_finish ();