[PATCH] Pass void_context_p to parse_expression
Tom Tromey
tromey@adacore.com
Fri Dec 18 15:12:18 GMT 2020
An earlier patch pointed out that nothing in GDB sets void_context_p
when parsing an expression. This patch fixes this omission.
"print" and "call" differ in that the former will print a value that
has void type, while the latter will not. AdaCore has had a patch for
a long time that uses this distinction to help with overload
resolution. In particular, in a "call" context, a procedure will be
chosen, while in a "print" context, a zero-argument function will be
chosen instead.
Regression tested on x86-64 Fedora 32.
gdb/ChangeLog
2020-12-18 Tom Tromey <tromey@adacore.com>
* parse.c (parse_expression): Add void_context_p parameter. Use
parse_exp_in_context.
* printcmd.c (print_command_1): Change voidprint to bool. Pass to
parse_expression.
(print_command, call_command): Update.
* expression.h (parse_expression): Add void_context_p parameter.
gdb/testsuite/ChangeLog
2020-12-18 Tom Tromey <tromey@adacore.com>
* gdb.ada/voidctx/pck.adb: New file.
* gdb.ada/voidctx/pck.ads: New file.
* gdb.ada/voidctx/voidctx.adb: New file.
* gdb.ada/voidctx.exp: New file.
---
gdb/ChangeLog | 9 +++++++
gdb/expression.h | 3 ++-
gdb/parse.c | 15 ++++++++---
gdb/printcmd.c | 10 ++++---
gdb/testsuite/ChangeLog | 7 +++++
gdb/testsuite/gdb.ada/voidctx.exp | 33 +++++++++++++++++++++++
gdb/testsuite/gdb.ada/voidctx/pck.adb | 26 ++++++++++++++++++
gdb/testsuite/gdb.ada/voidctx/pck.ads | 19 +++++++++++++
gdb/testsuite/gdb.ada/voidctx/voidctx.adb | 31 +++++++++++++++++++++
9 files changed, 144 insertions(+), 9 deletions(-)
create mode 100644 gdb/testsuite/gdb.ada/voidctx.exp
create mode 100644 gdb/testsuite/gdb.ada/voidctx/pck.adb
create mode 100644 gdb/testsuite/gdb.ada/voidctx/pck.ads
create mode 100644 gdb/testsuite/gdb.ada/voidctx/voidctx.adb
diff --git a/gdb/expression.h b/gdb/expression.h
index c07111c316f..2abf2d280d6 100644
--- a/gdb/expression.h
+++ b/gdb/expression.h
@@ -120,7 +120,8 @@ typedef std::unique_ptr<expression> expression_up;
class innermost_block_tracker;
extern expression_up parse_expression (const char *,
- innermost_block_tracker * = nullptr);
+ innermost_block_tracker * = nullptr,
+ bool void_context_p = false);
extern expression_up parse_expression_with_language (const char *string,
enum language lang);
diff --git a/gdb/parse.c b/gdb/parse.c
index 80a67c6c707..1d98a6d9e0c 100644
--- a/gdb/parse.c
+++ b/gdb/parse.c
@@ -1158,13 +1158,20 @@ parse_exp_in_context (const char **stringptr, CORE_ADDR pc,
return result;
}
-/* Parse STRING as an expression, and complain if this fails
- to use up all of the contents of STRING. */
+/* Parse STRING as an expression, and complain if this fails to use up
+ all of the contents of STRING. TRACKER, if non-null, will be
+ updated by the parser. VOID_CONTEXT_P should be true to indicate
+ that the expression may be expected to return a value with void
+ type. Parsers are free to ignore this, or to use it to help with
+ overload resolution decisions. */
expression_up
-parse_expression (const char *string, innermost_block_tracker *tracker)
+parse_expression (const char *string, innermost_block_tracker *tracker,
+ bool void_context_p)
{
- expression_up exp = parse_exp_1 (&string, 0, 0, 0, tracker);
+ expression_up exp = parse_exp_in_context (&string, 0, nullptr, 0,
+ void_context_p, nullptr,
+ tracker, nullptr);
if (*string)
error (_("Junk after end of expression."));
return exp;
diff --git a/gdb/printcmd.c b/gdb/printcmd.c
index de083a2a768..2de5f32cc7c 100644
--- a/gdb/printcmd.c
+++ b/gdb/printcmd.c
@@ -1206,7 +1206,7 @@ print_value (value *val, const value_print_options &opts)
/* Implementation of the "print" and "call" commands. */
static void
-print_command_1 (const char *args, int voidprint)
+print_command_1 (const char *args, bool voidprint)
{
struct value *val;
value_print_options print_opts;
@@ -1223,7 +1223,9 @@ print_command_1 (const char *args, int voidprint)
if (exp != nullptr && *exp)
{
- expression_up expr = parse_expression (exp);
+ /* VOIDPRINT is true to indicate that we do want to print a void
+ value, so invert it for parse_expression. */
+ expression_up expr = parse_expression (exp, nullptr, !voidprint);
val = evaluate_expression (expr.get ());
}
else
@@ -1321,14 +1323,14 @@ print_command_completer (struct cmd_list_element *ignore,
static void
print_command (const char *exp, int from_tty)
{
- print_command_1 (exp, 1);
+ print_command_1 (exp, true);
}
/* Same as print, except it doesn't print void results. */
static void
call_command (const char *exp, int from_tty)
{
- print_command_1 (exp, 0);
+ print_command_1 (exp, false);
}
/* Implementation of the "output" command. */
diff --git a/gdb/testsuite/gdb.ada/voidctx.exp b/gdb/testsuite/gdb.ada/voidctx.exp
new file mode 100644
index 00000000000..7e38cad0f7e
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/voidctx.exp
@@ -0,0 +1,33 @@
+# Copyright 2020 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 voidctx
+
+if {[gdb_compile_ada "${srcfile}" "${binfile}" executable [list debug ]] != "" } {
+ return -1
+}
+
+clean_restart ${testfile}
+
+set bp_location [gdb_get_line_number "STOP" ${testdir}/voidctx.adb]
+runto "voidctx.adb:$bp_location"
+
+gdb_test "print DoSomething" " = 42"
+gdb_test_no_output "call DoSomething"
+
diff --git a/gdb/testsuite/gdb.ada/voidctx/pck.adb b/gdb/testsuite/gdb.ada/voidctx/pck.adb
new file mode 100644
index 00000000000..5b8bdfe6a29
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/voidctx/pck.adb
@@ -0,0 +1,26 @@
+-- Copyright 2020 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 body Pck is
+ function DoSomething return Integer is
+ begin
+ return 42;
+ end;
+
+ procedure DoSomething is
+ begin
+ null;
+ end;
+end Pck;
diff --git a/gdb/testsuite/gdb.ada/voidctx/pck.ads b/gdb/testsuite/gdb.ada/voidctx/pck.ads
new file mode 100644
index 00000000000..71d891a9bea
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/voidctx/pck.ads
@@ -0,0 +1,19 @@
+-- Copyright 2020 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 Pck is
+ function DoSomething return Integer;
+ procedure DoSomething;
+end Pck;
diff --git a/gdb/testsuite/gdb.ada/voidctx/voidctx.adb b/gdb/testsuite/gdb.ada/voidctx/voidctx.adb
new file mode 100644
index 00000000000..fcf7af73f05
--- /dev/null
+++ b/gdb/testsuite/gdb.ada/voidctx/voidctx.adb
@@ -0,0 +1,31 @@
+-- Copyright 2020 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 Pck; use Pck;
+procedure Voidctx is
+
+ function DoSomething return Integer is
+ begin
+ return 42;
+ end;
+
+ procedure DoSomething is
+ begin
+ null;
+ end;
+
+begin
+ null; -- STOP
+end Voidctx;
--
2.26.2
More information about the Gdb-patches
mailing list