[PATCH] [PR GDB/32398] Fix name resolution for imported D modules

[liushuyu]

This fixes the name lookup regression since GDB 10 for the D language
where if an import is nested inside a function declaration, the lookup
will fail due to scope information is missing.
---
 gdb/dwarf2/read.c                   |  6 ++
 gdb/testsuite/gdb.dlang/imports.c   | 34 +++++++++++
 gdb/testsuite/gdb.dlang/imports.exp | 88 +++++++++++++++++++++++++++++
 3 files changed, 128 insertions(+)
 create mode 100644 gdb/testsuite/gdb.dlang/imports.c
 create mode 100644 gdb/testsuite/gdb.dlang/imports.exp

diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index 1ae56d3fb5..48bb09b2b0 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -20377,6 +20377,12 @@ determine_prefix (struct die_info *die, struct dwarf2_cu *cu)
 	    else if (die->tag == DW_TAG_entry_point)
 	      return determine_prefix (parent, cu);
 	  }
+	/* Imports in D langauge might be nested inside functions or delegates.
+	   We will bubble up through the tree to find the module name. */
+	if (cu->lang () == language_d)
+	  {
+	    return determine_prefix (parent, cu);
+	  }
 	return "";
       case DW_TAG_enumeration_type:
 	parent_type = read_type_die (parent, cu);
diff --git a/gdb/testsuite/gdb.dlang/imports.c b/gdb/testsuite/gdb.dlang/imports.c
new file mode 100644
index 0000000000..8a91f30d0c
--- /dev/null
+++ b/gdb/testsuite/gdb.dlang/imports.c
@@ -0,0 +1,34 @@
+/* Copyright 2017-2024 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* DWARF will describe these contents as being inside a D module.  */
+float _D6import6b_Globf = 55.22;
+
+int
+_Dmain (void)
+{
+  asm ("_Dmain_label: .globl _Dmain_label");
+  _D6import6b_Globf = 0.125;
+  asm ("_Dmain_break_label: .globl _Dmain_break_label");
+  return 0;
+}
+
+asm ("_Dmain_end: .globl _Dmain_end");
+
+int
+main (void)
+{
+  return _Dmain ();
+}
diff --git a/gdb/testsuite/gdb.dlang/imports.exp b/gdb/testsuite/gdb.dlang/imports.exp
new file mode 100644
index 0000000000..936ee94bba
--- /dev/null
+++ b/gdb/testsuite/gdb.dlang/imports.exp
@@ -0,0 +1,88 @@
+# Copyright (C) 2017-2024 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Test symbol lookup when there are multiple circular imports.
+
+load_lib "d-support.exp"
+load_lib "dwarf.exp"
+
+require allow_d_tests dwarf2_support
+
+standard_testfile imports.c imports-dw.S
+
+lassign [function_range _Dmain ${srcdir}/${subdir}/${srcfile}] \
+    dmain_start dmain_length
+
+
+# Make some DWARF for the test.
+set asm_file [standard_output_file $srcfile2]
+Dwarf::assemble $asm_file {
+    global dmain_start dmain_length
+
+    cu { label cu_start } {
+	compile_unit {
+	    {language @DW_LANG_D}
+	} {
+	    declare_labels main_module_label imported_module_label float_label
+            
+            float_label: base_type {
+		{name float}
+		{encoding @DW_ATE_float}
+		{byte_size 4 DW_FORM_sdata}
+	    }
+
+            imported_module_label: module {
+                {name import}
+            } {
+                tag_variable {
+                    {name b_Globf}
+                    {MIPS_linkage_name _D6import6b_Globf}
+                    {external 1 flag}
+                    {type :$float_label}
+                }
+            }
+
+	    main_module_label: module {
+		{name main}
+	    } {
+		subprogram {
+		    {MACRO_AT_func { "_Dmain" }}
+		    {external 1 flag_present}
+		} {
+                    imported_module {
+                        { import :$imported_module_label } 
+                    } 
+                }
+	    }
+	}
+    }
+
+    aranges {} cu_start {
+	arange {} $dmain_start $dmain_length
+    }
+}
+
+if { [prepare_for_testing "failed to prepare" ${testfile} \
+          [list $srcfile $asm_file] {nodebug}] } {
+    return -1
+}
+
+gdb_test_no_output "set language d"
+
+if {![runto "_Dmain_break_label"]} {
+    return -1
+}
+
+gdb_test "print b_Glob" "= 0.125"
-- 
2.47.1