gdb/testsuite/gdb.base/step-over-no-symbols.exp

# Copyright (C) 2015-2021 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 that GDB can step past a breakpoint even if GDB doesn't have
# symbols for the main binary.  PR gdb/13858.

standard_testfile start.c

if { [build_executable "failed to build" ${testfile} $srcfile] } {
    return -1
}

# Get the current PC.  MSG is used as test message.

proc get_pc { msg } {
    global hex gdb_prompt

    set addr ""
    gdb_test_multiple "p /x \$pc" "$msg" {
	-re " = ($hex).*$gdb_prompt $" {
	    set addr $expect_out(1,string)
	    pass "$msg"
	}
    }

    return $addr
}

# Test stepping past a breakpoint with no symbols.  DISPLACED is one
# of the "set displaced-stepping" options.  If GDB can't find where to
# put the scratch pad, GDB should be able to fall back to stepping
# past the breakpoint using an in-line step-over.

proc test_step_over { displaced } {
    global hex
    global binfile

    clean_restart $binfile

    if ![runto_main] {
	return -1
    }

    delete_breakpoints

    set msg "purging symbols"
    gdb_test_multiple "file" "$msg" {
	-re "Are you sure you want to change the file.*y or n. $" {
	    send_gdb "y\n"
	    exp_continue
	}
	-re "Discard symbol table.*y or n. $" {
	    gdb_test "y" "No symbol file now." "$msg"
	}
    }

    set before_addr [get_pc "get before PC"]

    gdb_test "break *\$pc" "Breakpoint .* at $hex"

    gdb_test_no_output "set displaced-stepping $displaced"

    gdb_test "stepi" "$hex in \?\? .*"

    set after_addr [get_pc "get after PC"]

    gdb_assert {{[regexp "^${hex}$" $before_addr] \
		 && [regexp "^${hex}$" $after_addr] \
		 && $before_addr != $after_addr}} "advanced"
}

foreach displaced { "off" "on" "auto" } {
    if { $displaced != "off" && ![support_displaced_stepping] } {
	continue
    }

    with_test_prefix "displaced=$displaced" {
	test_step_over $displaced
    }
}