From 919e6dbe9b61a27e8f7f89121ba182907df461a3 Mon Sep 17 00:00:00 2001 From: Pierre-Marie de Rodat Date: Fri, 4 Sep 2015 13:09:00 +0200 Subject: [PATCH] [Ada] Fix the evaluation of access to packed array subscript This change is relevant only for standard DWARF (as opposed to the GNAT encodings extensions): at the time of writing it only makes a difference with GCC patches that are to be integrated: see in particular . Given the following Ada declarations: type Small is mod 2 ** 6; type Array_Type is array (0 .. 9) of Small with Pack; type Array_Access is access all Array_Type; A : aliased Array_Type := (1, 2, 3, 4, 5, 6, 7, 8, 9, 10); AA : constant Array_Type := A'Access; Before this change, we would get the following GDB session: (gdb) print aa.all(2) $1 = 3 (gdb) print aa(2) $2 = 16 This is wrong: both expression should yield the same value: 3. The problem is simply that the routine which handles accesses to arrays lack general handling for packed arrays. After this patch, we have the expected output: (gdb) print aa.all(2) $1 = 3 (gdb) print aa(2) $2 = 3 gdb/ChangeLog: * ada-lang.c (ada_value_ptr_subscript): Update the heading comment. Handle packed arrays. gdb/testsuite/ChangeLog: * gdb.ada/access_to_packed_array.exp: New testcase. * gdb.ada/access_to_packed_array/foo.adb: New file. * gdb.ada/access_to_packed_array/pack.adb: New file. * gdb.ada/access_to_packed_array/pack.ads: New file. Tested on x86_64-linux, no regression. --- gdb/ChangeLog | 5 ++++ gdb/ada-lang.c | 17 +++++++++-- gdb/testsuite/ChangeLog | 7 +++++ gdb/testsuite/gdb.ada/access_to_packed_array.exp | 33 ++++++++++++++++++++++ .../gdb.ada/access_to_packed_array/foo.adb | 21 ++++++++++++++ .../gdb.ada/access_to_packed_array/pack.adb | 23 +++++++++++++++ .../gdb.ada/access_to_packed_array/pack.ads | 29 +++++++++++++++++++ 7 files changed, 133 insertions(+), 2 deletions(-) create mode 100644 gdb/testsuite/gdb.ada/access_to_packed_array.exp create mode 100644 gdb/testsuite/gdb.ada/access_to_packed_array/foo.adb create mode 100644 gdb/testsuite/gdb.ada/access_to_packed_array/pack.adb create mode 100644 gdb/testsuite/gdb.ada/access_to_packed_array/pack.ads diff --git a/gdb/ChangeLog b/gdb/ChangeLog index dadb7a0..3ca1bf1 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +2015-09-14 Pierre-Marie de Rodat + + * ada-lang.c (ada_value_ptr_subscript): Update the heading + comment. Handle packed arrays. + 2015-09-14 Pedro Alves * NEWS (Changes in GDB 7.10, New commands>: Remove duplicate diff --git a/gdb/ada-lang.c b/gdb/ada-lang.c index d166d1c..49f3d9a 100644 --- a/gdb/ada-lang.c +++ b/gdb/ada-lang.c @@ -2757,14 +2757,27 @@ ada_value_subscript (struct value *arr, int arity, struct value **ind) /* Assuming ARR is a pointer to a GDB array, the value of the element of *ARR at the ARITY indices given in IND. - Does not read the entire array into memory. */ + Does not read the entire array into memory. + + Note: Unlike what one would expect, this function is used instead of + ada_value_subscript for basically all non-packed array types. The reason + for this is that a side effect of doing our own pointer arithmetics instead + of relying on value_subscript is that there is no implicit typedef peeling. + This is important for arrays of array accesses, where it allows us to + preserve the fact that the array's element is an array access, where the + access part os encoded in a typedef layer. */ static struct value * ada_value_ptr_subscript (struct value *arr, int arity, struct value **ind) { int k; + struct value *array_ind = ada_value_ind (arr); struct type *type - = check_typedef (value_enclosing_type (ada_value_ind (arr))); + = check_typedef (value_enclosing_type (array_ind)); + + if (TYPE_CODE (type) == TYPE_CODE_ARRAY + && TYPE_FIELD_BITSIZE (type, 0) > 0) + return value_subscript_packed (array_ind, arity, ind); for (k = 0; k < arity; k += 1) { diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index e135b56..17b264d 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,10 @@ +2015-09-14 Pierre-Marie de Rodat + + * gdb.ada/access_to_packed_array.exp: New testcase. + * gdb.ada/access_to_packed_array/foo.adb: New file. + * gdb.ada/access_to_packed_array/pack.adb: New file. + * gdb.ada/access_to_packed_array/pack.ads: New file. + 2015-09-14 Markus Metzger * gdb.btrace/buffer-size.exp: Remove recording with unlimited BTS diff --git a/gdb/testsuite/gdb.ada/access_to_packed_array.exp b/gdb/testsuite/gdb.ada/access_to_packed_array.exp new file mode 100644 index 0000000..0dca780 --- /dev/null +++ b/gdb/testsuite/gdb.ada/access_to_packed_array.exp @@ -0,0 +1,33 @@ +# Copyright 2015 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 . + +load_lib "ada.exp" + +standard_ada_testfile foo + +if {[gdb_compile_ada "${srcfile}" "${binfile}" executable [list debug]] != "" } { + return -1 +} + +clean_restart ${testfile} + +set bp_location [gdb_get_line_number "BREAK" ${testdir}/foo.adb] +runto "foo.adb:$bp_location" + +gdb_test "print pack.a" "\\(0 => 1, 2, 3, 4, 5, 6, 7, 8, 9, 10\\)") +gdb_test "pack.aa" "\\(access pack\\.array_type\\) 0x.* ") + +gdb_test "pack.a(2)" "3" +gdb_test "pack.aa(2)" "3" diff --git a/gdb/testsuite/gdb.ada/access_to_packed_array/foo.adb b/gdb/testsuite/gdb.ada/access_to_packed_array/foo.adb new file mode 100644 index 0000000..71ae5bf --- /dev/null +++ b/gdb/testsuite/gdb.ada/access_to_packed_array/foo.adb @@ -0,0 +1,21 @@ +-- Copyright 2015 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 . + +with Pack; + +procedure Foo is +begin + Pack.Do_Nothing (Pack.AA); -- BREAK +end Foo; diff --git a/gdb/testsuite/gdb.ada/access_to_packed_array/pack.adb b/gdb/testsuite/gdb.ada/access_to_packed_array/pack.adb new file mode 100644 index 0000000..60d752d --- /dev/null +++ b/gdb/testsuite/gdb.ada/access_to_packed_array/pack.adb @@ -0,0 +1,23 @@ +-- Copyright 2015 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 . + +package body Pack is + + procedure Do_Nothing (A : Array_Access) is + begin + null; + end Do_Nothing; + +end Pack; diff --git a/gdb/testsuite/gdb.ada/access_to_packed_array/pack.ads b/gdb/testsuite/gdb.ada/access_to_packed_array/pack.ads new file mode 100644 index 0000000..bb08742 --- /dev/null +++ b/gdb/testsuite/gdb.ada/access_to_packed_array/pack.ads @@ -0,0 +1,29 @@ +-- Copyright 2015 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 . + +package Pack is + + type Small is mod 2 ** 6; + type Array_Type is array (0 .. 9) of Small + with Pack; + type Array_Access is access all Array_Type; + + A : aliased Array_Type := + (1, 2, 3, 4, 5, 6, 7, 8, 9, 10); + AA : constant Array_Access := A'Access; + + procedure Do_Nothing (A : Array_Access); + +end Pack; -- 2.7.4