gdb/testsuite/gdb.base/break-fun-addr.exp

# Copyright 2016-2021 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/>.

# The purpose of this testcase is to verify that, when using a breakpoint
# location of the form "*<EXPR>" (Eg: "*main"), GDB is able to start
# the program and stop at the correct location.  With programs built
# as PIE, this means that GDB needs to re-evaluate the location once
# the program as started, since PIE ensures that the address of all
# symbols have changed after load.
#
# PIE is not always supported by the target system, so instead of
# creating a testcase building executables with PIE, this testcase
# takes a slightly different approach.  It builds a first program,
# breaks on *main, and then runs to that breakpoint. It then builds
# a second program, different from the first one, and loads that
# executable within the same GDB session.  Similarly to the PIE case,
# the address of main should be different, and therefore GDB should
# recalculate it.  We verify that by checking that running to that
# breakpoint still works, and that we land at the first instruction
# of that function in both cases.

set testfile1 "break-fun-addr1"
set srcfile1 ${testfile1}.c
set binfile1 [standard_output_file ${testfile1}]

if  { [gdb_compile "${srcdir}/${subdir}/${srcfile1}" "${binfile1}" executable {debug}] != "" } {
    untested "failed to compile first testcase"
    return -1
}

# Start the debugger with the first executable, put a breakpoint
# on the first instruction of function "main" ("*main"), then
# run to that breakpoint.

clean_restart ${binfile1}

with_test_prefix "${testfile1}" {

    gdb_test "break *main" \
        "Breakpoint.*at.* file .*$srcfile1, line .*" \

    gdb_run_cmd
    gdb_test "" \
             "Breakpoint.* main \\(\\) at .*$srcfile1:.*" \
             "run to breakpoint at *main"

    # Verify also that we stopped at the start of the function...
    gdb_test "p \$pc == main" " = 1"
}

set testfile2 "break-fun-addr2"
set srcfile2 ${testfile2}.c
set binfile2 [standard_output_file ${testfile2}]

if  { [gdb_compile "${srcdir}/${subdir}/${srcfile2}" "${binfile2}" executable {debug}] != "" } {
    untested "failed to compile second testcase"
    return -1
}

# Now, keeping the same GDB process (so as to keep the same breakpoint),
# start a new debugging session with a different executable.
gdb_load ${binfile2}

with_test_prefix "${testfile2}" {

    gdb_run_cmd
    gdb_test "" \
             "Breakpoint.* main \\(\\) at .*$srcfile2:.*" \
             "run to breakpoint at *main"

    gdb_test "p \$pc == main" " = 1"
}