[v2,3/3] GDB: Add `info main' command
Commit Message
From: Richard Bunt <richard.bunt@linaro.org>
Allow consumers of GDB to extract the name of the main method. This is
most useful for Fortran programs which have a variable main method.
Used by both MAP and DDT e.g. it is used to detect the presence of debug
information.
Co-Authored-By: Maciej W. Rozycki <macro@embecosm.com>
---
Changes from v1:
- Add documentation pieces.
---
gdb/NEWS | 3 ++
gdb/doc/gdb.texinfo | 6 ++++
gdb/symtab.c | 11 ++++++++
gdb/testsuite/gdb.fortran/info-main.exp | 42 ++++++++++++++++++++++++++++++++
gdb/testsuite/gdb.fortran/info-main.f90 | 19 ++++++++++++++
5 files changed, 81 insertions(+)
gdb-richard-info-main-command.diff
Comments
> Date: Tue, 28 Mar 2023 19:49:02 +0100 (BST)
> From: "Maciej W. Rozycki" <macro@embecosm.com>
> cc: Richard Bunt <richard.bunt@linaro.org>
>
> From: Richard Bunt <richard.bunt@linaro.org>
>
> Allow consumers of GDB to extract the name of the main method. This is
> most useful for Fortran programs which have a variable main method.
>
> Used by both MAP and DDT e.g. it is used to detect the presence of debug
> information.
>
> Co-Authored-By: Maciej W. Rozycki <macro@embecosm.com>
> ---
> Changes from v1:
>
> - Add documentation pieces.
> ---
> gdb/NEWS | 3 ++
> gdb/doc/gdb.texinfo | 6 ++++
> gdb/symtab.c | 11 ++++++++
> gdb/testsuite/gdb.fortran/info-main.exp | 42 ++++++++++++++++++++++++++++++++
> gdb/testsuite/gdb.fortran/info-main.f90 | 19 ++++++++++++++
> 5 files changed, 81 insertions(+)
Thanks, the documentation parts are OK.
Reviewed-By: Eli Zaretskii <eliz@gnu.org>
===================================================================
@@ -83,6 +83,9 @@ show always-read-ctf
When off, CTF is only read if DWARF is not present. When on, CTF is
read regardless of whether DWARF is present. Off by default.
+info main
+ Get main symbol to identify entry point into program.
+
* New convenience function "$_shell", to execute a shell command and
return the result. This lets you run shell commands in expressions.
Some examples:
===================================================================
@@ -20162,6 +20162,12 @@ The optional flag @samp{-q}, which stand
printing header information and messages explaining why no functions
or variables have been printed.
+@kindex info main
+@item info main
+Print the name of the starting function of the program. This serves
+primarily Fortran programs, which have a user-supplied name for the
+main subroutine.
+
@kindex info classes
@cindex Objective-C, classes and selectors
@item info classes
===================================================================
@@ -5282,6 +5282,14 @@ info_modules_command (const char *args,
from_tty);
}
+/* Implement the 'info main' command. */
+
+static void
+info_main_command (const char *args, int from_tty)
+{
+ gdb_printf ("%s\n", main_name ());
+}
+
static void
rbreak_command (const char *regexp, int from_tty)
{
@@ -6873,6 +6881,9 @@ Options:\n\
_("All module names, or those matching REGEXP."));
set_cmd_completer_handle_brkchars (c, info_types_command_completer);
+ add_info ("main", info_main_command,
+ _("Get main symbol to identify entry point into program."));
+
add_basic_prefix_cmd ("module", class_info, _("\
Print information about modules."),
&info_module_cmdlist, 0, &infolist);
===================================================================
@@ -0,0 +1,42 @@
+# Copyright 2023 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/>.
+
+require allow_fortran_tests
+
+load_lib fortran.exp
+
+standard_testfile .f90
+
+set old_gdbflags $GDBFLAGS
+set GDBFLAGS [string map {"-readnow" ""} "$GDBFLAGS"]
+
+if {[prepare_for_testing ${testfile}.exp ${testfile} ${srcfile} {debug f90}]} {
+ return -1
+}
+
+gdb_test "info main" "simple" "info main prior to start"
+
+if ![fortran_runto_main] {
+ untested "could not run to main"
+ return -1
+}
+
+gdb_test "info main" "simple" "info main post start"
+
+set GDBFLAGS "$GDBFLAGS -readnow"
+clean_restart $testfile
+gdb_test "info main" "simple" "info main with readnow"
+
+set GDBFLAGS $old_gdbflags
===================================================================
@@ -0,0 +1,19 @@
+! Copyright 2023 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/>.
+
+program simple
+ implicit none
+ print *, "Nothing."
+end program simple