[gcc r14-3421] debug/111080 - avoid outputting debug info for unused restrict qualified type

[gcc r14-3421] debug/111080 - avoid outputting debug info for unused restrict qualified type

[Richard Biener]

https://gcc.gnu.org/g:bd2c4d6d8fffd5a6dae5217d6076cc4190bab13d

commit r14-3421-gbd2c4d6d8fffd5a6dae5217d6076cc4190bab13d
Author: Richard Biener <rguenther@suse.de>
Date:   Mon Aug 21 10:34:30 2023 +0200

    debug/111080 - avoid outputting debug info for unused restrict qualified type
    
    The following applies some maintainance with respect to type qualifiers
    and kinds added by later DWARF standards to prune_unused_types_walk.
    The particular case in the bug is not handling (thus marking required)
    all restrict qualified type DIEs.  I've found more DW_TAG_*_type that
    are unhandled, looked up the DWARF docs and added them as well based
    on common sense.
    
            PR debug/111080
            * dwarf2out.cc (prune_unused_types_walk): Handle
            DW_TAG_restrict_type, DW_TAG_shared_type, DW_TAG_atomic_type,
            DW_TAG_immutable_type, DW_TAG_coarray_type, DW_TAG_unspecified_type
            and DW_TAG_dynamic_type as to only output them when referenced.
    
            * gcc.dg/debug/dwarf2/pr111080.c: New testcase.

Diff:
---
 gcc/dwarf2out.cc                             |  7 +++++++
 gcc/testsuite/gcc.dg/debug/dwarf2/pr111080.c | 18 ++++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/gcc/dwarf2out.cc b/gcc/dwarf2out.cc
index fa0fe4c41bbd..69018bde2383 100644
--- a/gcc/dwarf2out.cc
+++ b/gcc/dwarf2out.cc
@@ -30141,8 +30141,13 @@ prune_unused_types_walk (dw_die_ref die)
     case DW_TAG_reference_type:
     case DW_TAG_rvalue_reference_type:
     case DW_TAG_volatile_type:
+    case DW_TAG_restrict_type:
+    case DW_TAG_shared_type:
+    case DW_TAG_atomic_type:
+    case DW_TAG_immutable_type:
     case DW_TAG_typedef:
     case DW_TAG_array_type:
+    case DW_TAG_coarray_type:
     case DW_TAG_friend:
     case DW_TAG_enumeration_type:
     case DW_TAG_subroutine_type:
@@ -30151,6 +30156,8 @@ prune_unused_types_walk (dw_die_ref die)
     case DW_TAG_subrange_type:
     case DW_TAG_ptr_to_member_type:
     case DW_TAG_file_type:
+    case DW_TAG_unspecified_type:
+    case DW_TAG_dynamic_type:
       /* Type nodes are useful only when other DIEs reference them --- don't
 	 mark them.  */
       /* FALLTHROUGH */
diff --git a/gcc/testsuite/gcc.dg/debug/dwarf2/pr111080.c b/gcc/testsuite/gcc.dg/debug/dwarf2/pr111080.c
new file mode 100644
index 000000000000..3949d7e7c643
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/debug/dwarf2/pr111080.c
@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-options "-save-temps -gdwarf-3 -dA" } */
+
+struct foo {
+        int field_number_1;
+        int field_number_2;
+        int field_number_3;
+        int field_number_4;
+        int field_number_5;
+};
+
+typedef int fun_t(struct foo *restrict);
+
+int main() {
+        return 0;
+}
+
+/* { dg-final { scan-assembler-not "DW_TAG_structure_type" } } */