[PATCH] Do not emit a redundant DW_TAG_lexical_block for inlined subroutines

[Bernd Edlinger]

While this already works correctly for the case when an inlined
subroutine contains only one subrange, a redundant DW_TAG_lexical_block
is still emitted when the subroutine has multiple blocks.

Fixes: ac02e5b75451 ("re PR debug/37801 (DWARF output for inlined functions
                      doesn't always use DW_TAG_inlined_subroutine)")

gcc/ChangeLog:

        PR debug/87440
        * dwarf2out.cc (gen_inlined_subroutine_die): Handle the case
        of multiple subranges correctly.
---
some more context is here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87440#c5
Bootstrapped and regression-tested on x86_64-pc-linux-gnu, OK for trunk?

 gcc/dwarf2out.cc | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/gcc/dwarf2out.cc b/gcc/dwarf2out.cc
index 357efaa5990..346feeb53c8 100644
--- a/gcc/dwarf2out.cc
+++ b/gcc/dwarf2out.cc
@@ -25171,9 +25171,10 @@ gen_inlined_subroutine_die (tree stmt, dw_die_ref 
context_die)
      Do that by doing the recursion to subblocks on the single subblock
      of STMT.  */
   bool unwrap_one = false;
-  if (BLOCK_SUBBLOCKS (stmt) && !BLOCK_CHAIN (BLOCK_SUBBLOCKS (stmt)))
+  tree sub = BLOCK_SUBBLOCKS (stmt);
+  if (sub)
     {
-      tree origin = block_ultimate_origin (BLOCK_SUBBLOCKS (stmt));
+      tree origin = block_ultimate_origin (sub);
       if (origin
          && TREE_CODE (origin) == BLOCK
          && BLOCK_SUPERCONTEXT (origin) == decl)
@@ -25181,7 +25182,11 @@ gen_inlined_subroutine_die (tree stmt, dw_die_ref 
context_die)
     }
   decls_for_scope (stmt, subr_die, !unwrap_one);
   if (unwrap_one)
-    decls_for_scope (BLOCK_SUBBLOCKS (stmt), subr_die);
+    {
+      decls_for_scope (sub, subr_die);
+      for (sub = BLOCK_CHAIN (sub); sub; sub = BLOCK_CHAIN (sub))
+       gen_block_die (sub, subr_die);
+    }
 }
 
 /* Generate a DIE for a field in a record, or structure.  CTX is required: see
-- 
2.39.2