Restore DW_AT_abstract_origin for cross-unit call sites

PR debug/66503

gcc/ChangeLog:
	* debug.h (struct gcc_debug_hooks): Add a
	register_main_translation_unit hook.
	* debug.c (do_nothing_debug_hooks): Provide a function for this
	new hook.
	* dbxout.c (dbx_debug_hooks): Likewise.
	* sdbout.c (sdb_debug_hooks): Likewise.
	* vmsdbgout.c (vmsdbg_debug_hooks): Likewise.
	* dwarf2out.c (main_translation_unit): New global variable.
	(dwarf2out_register_main_translation_unit): New function
	implementing the new hook.
	(dwarf2_debug_hooks): Assign
	dwarf2out_register_main_translation_unit to this new hook.
	(dwarf2out_init): Associate any main translation unit to
	comp_unit_die ().
	* c/c-decl.c (pop_scope): Register the main translation unit
	through the new debug hook.
	* cp/decl.c (cxx_init_decl_processing): Likewise.

gcc/ada/ChangeLog:
	* gcc-interface/utils.c (get_global_context): Register the main
	translation unit through the new debug hook.

gcc/fortran/ChangeLog:
	* f95-lang.c (gfc_create_decls): Register the main translation
	unit through the new debug hook.

From-SVN: r224371

1 files changed, 27 insertions, 0 deletions

diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index ee2bcb1..8a36fe8 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -2446,6 +2446,7 @@ static void dwarf2out_abstract_function (tree);
 static void dwarf2out_var_location (rtx_insn *);
 static void dwarf2out_begin_function (tree);
 static void dwarf2out_end_function (unsigned int);
+static void dwarf2out_register_main_translation_unit (tree unit);
 static void dwarf2out_set_name (tree, tree);
 
 /* The debug hooks structure.  */
@@ -2475,6 +2476,7 @@ const struct gcc_debug_hooks dwarf2_debug_hooks =
   dwarf2out_end_epilogue,
   dwarf2out_begin_function,
   dwarf2out_end_function,	/* end_function */
+  dwarf2out_register_main_translation_unit,
   dwarf2out_function_decl,	/* function_decl */
   dwarf2out_early_global_decl,
   dwarf2out_late_global_decl,
@@ -22505,6 +22507,26 @@ dwarf2out_end_function (unsigned int)
   maybe_at_text_label_p = false;
 }
 
+/* Temporary holder for dwarf2out_register_main_translation_unit.  Used to let
+   front-ends register a translation unit even before dwarf2out_init is
+   called.  */
+static tree main_translation_unit = NULL_TREE;
+
+/* Hook called by front-ends after they built their main translation unit.
+   Associate comp_unit_die to UNIT.  */
+
+static void
+dwarf2out_register_main_translation_unit (tree unit)
+{
+  gcc_assert (TREE_CODE (unit) == TRANSLATION_UNIT_DECL
+	      && main_translation_unit == NULL_TREE);
+  main_translation_unit = unit;
+  /* If dwarf2out_init has not been called yet, it will perform the association
+     itself looking at main_translation_unit.  */
+  if (decl_die_table != NULL)
+    equate_decl_number_to_die (unit, comp_unit_die ());
+}
+
 /* Add OPCODE+VAL as an entry at the end of the opcode array in TABLE.  */
 
 static void
@@ -23242,6 +23264,11 @@ dwarf2out_init (const char *filename ATTRIBUTE_UNUSED)
   /* Make sure the line number table for .text always exists.  */
   text_section_line_info = new_line_info_table ();
   text_section_line_info->end_label = text_end_label;
+
+  /* If front-ends already registered a main translation unit but we were not
+     ready to perform the association, do this now.  */
+  if (main_translation_unit != NULL_TREE)
+    equate_decl_number_to_die (main_translation_unit, comp_unit_die ());
 }
 
 /* Called before compile () starts outputtting functions, variables