[PATCH] Remove array typedef assumption for Ada

[PATCH] Remove array typedef assumption for Ada

[Tom Tromey]

Currently the Ada code assumes that it can distinguish between a
multi-dimensional array and an array of arrays by looking for an
intervening typedef -- that is, for an array of arrays, there will be
a typedef wrapping the innermost array type.

A planned compiler change will remove this typedef, which causes a gdb
failure in the internal AdaCore test suite.

This patch handles this case by checking whether the array type in
question has a name.
---
 gdb/ada-lang.c                            |  6 +++
 gdb/ada-typeprint.c                       | 11 +++++-
 gdb/testsuite/gdb.ada/multiarray.exp      | 48 +++++++++++++++++++++++
 gdb/testsuite/gdb.ada/multiarray/p.adb    | 46 ++++++++++++++++++++++
 gdb/testsuite/gdb.ada/multiarray/pack.ads | 34 ++++++++++++++++
 5 files changed, 143 insertions(+), 2 deletions(-)
 create mode 100644 gdb/testsuite/gdb.ada/multiarray.exp
 create mode 100644 gdb/testsuite/gdb.ada/multiarray/p.adb
 create mode 100644 gdb/testsuite/gdb.ada/multiarray/pack.ads

diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c
index 93e0c67613f..650408134bb 100644
--- a/gdb/ada-lang.c
+++ b/gdb/ada-lang.c
@@ -3208,6 +3208,12 @@ ada_array_element_type (struct type *type, int nindices)
       while (nindices != 0 && type->code () == TYPE_CODE_ARRAY)
 	{
 	  type = TYPE_TARGET_TYPE (type);
+	  /* A multi-dimensional array is represented using a sequence
+	     of array types.  If one of these types has a name, then
+	     it is not another dimension of the outer array, but
+	     rather the element type of the outermost array.  */
+	  if (type->name () != nullptr)
+	    break;
 	  nindices -= 1;
 	}
       return type;
diff --git a/gdb/ada-typeprint.c b/gdb/ada-typeprint.c
index 05ffb8b8331..b402bfef523 100644
--- a/gdb/ada-typeprint.c
+++ b/gdb/ada-typeprint.c
@@ -377,8 +377,7 @@ print_array_type (struct type *type, struct ui_file *stream, int show,
       bitsize = 0;
       if (range_desc_type == NULL)
 	{
-	  for (arr_type = type; arr_type->code () == TYPE_CODE_ARRAY;
-	       arr_type = TYPE_TARGET_TYPE (arr_type))
+	  for (arr_type = type; arr_type->code () == TYPE_CODE_ARRAY; )
 	    {
 	      if (arr_type != type)
 		gdb_printf (stream, ", ");
@@ -386,6 +385,14 @@ print_array_type (struct type *type, struct ui_file *stream, int show,
 			   0 /* bounds_prefered_p */);
 	      if (TYPE_FIELD_BITSIZE (arr_type, 0) > 0)
 		bitsize = TYPE_FIELD_BITSIZE (arr_type, 0);
+	      /* A multi-dimensional array is represented using a
+		 sequence of array types.  If one of these types has a
+		 name, then it is not another dimension of the outer
+		 array, but rather the element type of the outermost
+		 array.  */
+	      arr_type = TYPE_TARGET_TYPE (arr_type);
+	      if (arr_type->name () != nullptr)
+		break;
 	    }
 	}
       else
diff --git a/gdb/testsuite/gdb.ada/multiarray.exp b/gdb/testsuite/gdb.ada/multiarray.exp
new file mode 100644
index 00000000000..bac16f2eee5
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/multiarray.exp
@@ -0,0 +1,48 @@
+# Copyright 2022 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/>.
+
+load_lib "ada.exp"
+
+if { [skip_ada_tests] } { return -1 }
+
+standard_ada_testfile p
+
+foreach_with_prefix scenario {all minimal} {
+    set flags [list debug additional_flags=-fgnat-encodings=$scenario]
+
+    if {[gdb_compile_ada "${srcfile}" "${binfile}" executable {debug}] != ""} {
+	return -1
+    }
+
+    clean_restart ${testfile}
+
+    set bp_location [gdb_get_line_number "START" ${testdir}/p.adb]
+    runto "p.adb:$bp_location"
+
+    gdb_test "ptype simple_type" \
+	[string_to_regexp "type = array (<>, <>) of integer"]
+    gdb_test "ptype nested_type" \
+	[string_to_regexp "type = array (<>, <>) of pack.ca_simple_type"]
+
+    gdb_test "ptype simple" \
+	[string_to_regexp "type = array (1 .. 3, 5 .. 6) of integer"]
+    gdb_test "ptype nested" \
+	[string_to_regexp "type = array (1 .. 3, 5 .. 6) of pack.ca_simple_type"]
+
+    gdb_test "print simple" \
+	[string_to_regexp " = ((5 => 1, 2), (5 => 3, 4), (5 => 5, 6))"]
+    gdb_test "print nested" \
+	[string_to_regexp " = ((5 => (1, 2), (3, 4)), (5 => (5, 6), (7, 8)), (5 => (9, 10), (11, 12)))"]
+}
diff --git a/gdb/testsuite/gdb.ada/multiarray/p.adb b/gdb/testsuite/gdb.ada/multiarray/p.adb
new file mode 100644
index 00000000000..eacc4063a90
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/multiarray/p.adb
@@ -0,0 +1,46 @@
+-- Copyright 2022 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/>.
+
+with Pack; use Pack;
+
+procedure P is
+
+   procedure Nop is
+   begin
+      null;
+   end Nop;
+
+   procedure Discard
+     (Arg_Simple  : Simple_Type;
+      Arg_Nested  : Nested_Type) is
+   begin
+      null;
+   end Discard;
+
+   Simple : Simple_Type :=
+      (1 => (5 => 1, 6 => 2),
+       2 => (5 => 3, 6 => 4),
+       3 => (5 => 5, 6 => 6));
+   Nested : Nested_Type :=
+      (1 => (5 => (1, 2),  6 => (3, 4)),
+       2 => (5 => (5, 6),  6 => (7, 8)),
+       3 => (5 => (9, 10), 6 => (11, 12)));
+
+begin
+   Nop; --  START
+
+   Discard (Simple, Nested);
+
+end P;
diff --git a/gdb/testsuite/gdb.ada/multiarray/pack.ads b/gdb/testsuite/gdb.ada/multiarray/pack.ads
new file mode 100644
index 00000000000..06091dea6a0
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/multiarray/pack.ads
@@ -0,0 +1,34 @@
+-- Copyright 2022 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/>.
+
+package Pack is
+
+   type Index_Type_1 is new Natural;
+   type Index_Type_2 is new Natural;
+   type Index_Type_3 is new Natural;
+
+   type CA_Simple_Type is array (Index_Type_1 range 1 .. 2) of Integer;
+
+   --  Array types we test
+
+   type Simple_Type is
+     array (Index_Type_1 range <>, Index_Type_2 range <>)
+     of Integer;
+
+   type Nested_Type is
+     array (Index_Type_1 range <>, Index_Type_2 range <>)
+     of CA_Simple_Type;
+
+end Pack;
-- 
2.34.1

Re: [PATCH] Remove array typedef assumption for Ada

[Tom Tromey]

>>>>> "Tom" == Tom Tromey via Gdb-patches <gdb-patches@sourceware.org> writes:

Tom> Currently the Ada code assumes that it can distinguish between a
Tom> multi-dimensional array and an array of arrays by looking for an
Tom> intervening typedef -- that is, for an array of arrays, there will be
Tom> a typedef wrapping the innermost array type.

Tom> A planned compiler change will remove this typedef, which causes a gdb
Tom> failure in the internal AdaCore test suite.

This patch went in to upstream GCC, so I am going to update this text
and push the patch.

Tom