* lib/gdb.exp(gdb_step_for_stub): New function.

[binutils-gdb.git] / gdb / testsuite / lib / gdb.exp

# Copyright (C) 1992, 1994, 1995, 1997 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 2 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, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  

# Please email any bugs, comments, and/or additions to this file to:
# bug-gdb@prep.ai.mit.edu

# This file was written by Fred Fish. (fnf@cygnus.com)

# Generic gdb subroutines that should work for any target.  If these
# need to be modified for any target, it can be done with a variable
# or by passing arguments.

load_lib libgloss.exp

global GDB
global CHILL_LIB
global CHILL_RT0

if ![info exists CHILL_LIB] {
    set CHILL_LIB [findfile $base_dir/../../gcc/ch/runtime/libchill.a "$base_dir/../../gcc/ch/runtime/libchill.a" [transform -lchill]]
}
verbose "using CHILL_LIB = $CHILL_LIB" 2
if ![info exists CHILL_RT0] {
    set CHILL_RT0 [findfile $base_dir/../../gcc/ch/runtime/chillrt0.o "$base_dir/../../gcc/ch/runtime/chillrt0.o" ""]
}
verbose "using CHILL_RT0 = $CHILL_RT0" 2

if [info exists TOOL_EXECUTABLE] {
    set GDB $TOOL_EXECUTABLE;
}
if ![info exists GDB] {
    if ![is_remote host] {
        set GDB [findfile $base_dir/../../gdb/gdb "$base_dir/../../gdb/gdb" [transform gdb]]
    } else {
        set GDB [transform gdb];
    }
}
verbose "using GDB = $GDB" 2

global GDBFLAGS
if ![info exists GDBFLAGS] {
    set GDBFLAGS "-nx"
}
verbose "using GDBFLAGS = $GDBFLAGS" 2

# The variable prompt is a regexp which matches the gdb prompt.  Set it if it
# is not already set.
global gdb_prompt
if ![info exists prompt] then {
    set gdb_prompt "\[(\]gdb\[)\]"
}

#
# gdb_version -- extract and print the version number of GDB
#
proc default_gdb_version {} {
    global GDB
    global GDBFLAGS
    global gdb_prompt
    set fileid [open "gdb_cmd" w];
    puts $fileid "q";
    close $fileid;
    set cmdfile [remote_download host "gdb_cmd"];
    set output [remote_exec host "$GDB -nw --command $cmdfile"]
    remote_file build delete "gdb_cmd";
    remote_file host delete "$cmdfile";
    set tmp [lindex $output 1];
    set version ""
    regexp " \[0-9\]\[^ \t\n\r\]+" "$tmp" version
    if ![is_remote host] {
        clone_output "[which $GDB] version $version $GDBFLAGS\n"
    } else {
        clone_output "$GDB on remote host version $version $GDBFLAGS\n"
    }
}

proc gdb_version { } {
    return [default_gdb_version];
}

#
# gdb_unload -- unload a file if one is loaded
#

proc gdb_unload {} {
    global verbose
    global GDB
    global gdb_prompt
    send_gdb "file\n"
    gdb_expect 60 {
        -re "No exec file now\[^\r\n\]*\[\r\n\]" { exp_continue }
        -re "No symbol file now\[^\r\n\]*\[\r\n\]" { exp_continue }
        -re "A program is being debugged already..*Kill it.*y or n. $"\
            { send_gdb "y\n"
                verbose "\t\tKilling previous program being debugged"
            exp_continue
        }
        -re "Discard symbol table from .*y or n.*$" {
            send_gdb "y\n"
            exp_continue
        }
        -re "$gdb_prompt $" {}
        timeout {
            perror "couldn't unload file in $GDB (timed out)."
            return -1
        }
    }
}

# Many of the tests depend on setting breakpoints at various places and
# running until that breakpoint is reached.  At times, we want to start
# with a clean-slate with respect to breakpoints, so this utility proc 
# lets us do this without duplicating this code everywhere.
#

proc delete_breakpoints {} {
    global gdb_prompt

    send_gdb "delete breakpoints\n"
    gdb_expect 30 {
         -re "Delete all breakpoints.*y or n.*$" {
            send_gdb "y\n";
            exp_continue
        }
         -re "$gdb_prompt $" { # This happens if there were no breakpoints
            }
         timeout { perror "Delete all breakpoints in delete_breakpoints (timeout)" ; return }
    }
    send_gdb "info breakpoints\n"
    gdb_expect 30 {
         -re "No breakpoints or watchpoints..*$gdb_prompt $" {}
         -re "$gdb_prompt $" { perror "breakpoints not deleted" ; return }
         -re "Delete all breakpoints.*or n.*$" {
            send_gdb "y\n";
            exp_continue
        }
         timeout { perror "info breakpoints (timeout)" ; return }
    }
}


#
# Generic run command.
#
# The second pattern below matches up to the first newline *only*.
# Using ``.*$'' could swallow up output that we attempt to match
# elsewhere.
#
proc gdb_run_cmd {args} {
    global gdb_prompt

    if [target_info exists gdb_init_command] {
        send_gdb "[target_info gdb_init_command]\n";
        gdb_expect 30 {
            -re "$gdb_prompt $" { }
            default {
                perror "gdb_init_command for target failed";
                return;
            }
        }
    }

    if [target_info exists use_gdb_stub] {
        if [target_info exists gdb,do_reload_on_run] {
            # According to Stu, this will always work.
            gdb_load "";
            send_gdb "continue\n";
            gdb_expect 60 {
                -re "Continu\[^\r\n\]*\[\r\n\]" {}
                default {}
            }
            return;
        }

        if [target_info exists gdb,start_symbol] {
            set start [target_info gdb,start_symbol];
        } else {
            set start "start";
        }
        send_gdb  "jump *$start\n"
        gdb_expect 30 {
            -re "Continuing at \[^\r\n\]*\[\r\n\]" {
                if ![target_info exists gdb_stub] {
                    return;
                }
            }
            -re "No symbol \"start\" in current.*$gdb_prompt $" {
                send_gdb "jump *_start\n";
                exp_continue;
            }
            -re "No symbol \"_start\" in current.*$gdb_prompt $" {
                perror "Can't find start symbol to run in gdb_run";
                return;
            }
            -re "Line.* Jump anyway.*y or n. $" {
                send_gdb "y\n"
                exp_continue;
            }
            -re "No symbol.*context.*$gdb_prompt $" {}
            -re "The program is not being run.*$gdb_prompt $" {
                gdb_load "";
                send_gdb "jump *$start\n";
                exp_continue;
            }
            timeout { perror "Jump to start() failed (timeout)"; return }
        }
        if [target_info exists gdb_stub] {
            gdb_expect 60 {
                -re "$gdb_prompt $" {
                    send_gdb "continue\n"
                }
            }
        }
        return
    }
    send_gdb "run $args\n"
# This doesn't work quite right yet.
    gdb_expect 60 {
        -re "The program .* has been started already.*y or n. $" {
            send_gdb "y\n"
            exp_continue
        }
        -re "Starting program: \[^\r\n\]*" {}
    }
}

proc gdb_breakpoint { function } {
    global gdb_prompt
    global decimal

    send_gdb "break $function\n"
    # The first two regexps are what we get with -g, the third is without -g.
    gdb_expect 30 {
        -re "Breakpoint \[0-9\]* at .*: file .*, line $decimal.\r\n$gdb_prompt $" {}
        -re "Breakpoint \[0-9\]*: file .*, line $decimal.\r\n$gdb_prompt $" {}
        -re "Breakpoint \[0-9\]* at .*$gdb_prompt $" {}
        -re "$gdb_prompt $" { fail "setting breakpoint at $function" ; return 0 }
        timeout { fail "setting breakpoint at $function (timeout)" ; return 0 }
    }
    return 1;
}    

# Set breakpoint at function and run gdb until it breaks there.
# Since this is the only breakpoint that will be set, if it stops
# at a breakpoint, we will assume it is the one we want.  We can't
# just compare to "function" because it might be a fully qualified,
# single quoted C++ function specifier.

proc runto { function } {
    global gdb_prompt
    global decimal

    delete_breakpoints

    if ![gdb_breakpoint $function] {
        return 0;
    }

    gdb_run_cmd
    
    # the "at foo.c:36" output we get with -g.
    # the "in func" output we get without -g.
    gdb_expect 30 {
        -re "Break.* at .*:$decimal.*$gdb_prompt $" {
            return 1
        }
        -re "Breakpoint \[0-9\]*, \[0-9xa-f\]* in .*$gdb_prompt $" { 
            return 1
        }
        -re "$gdb_prompt $" { 
            fail "running to $function in runto"
            return 0
        }
        timeout { 
            fail "running to $function in runto (timeout)"
            return 0
        }
    }
    return 1
}

#
# runto_main -- ask gdb to run until we hit a breakpoint at main.
#               The case where the target uses stubs has to be handled
#               specially--if it uses stubs, assuming we hit
#               breakpoint() and just step out of the function.
#
proc runto_main { } {
    global gdb_prompt
    global decimal

    if ![target_info exists gdb_stub] {
        return [runto main]
    }                   

    delete_breakpoints

    gdb_step_for_stub;

    return 1
}

#
# gdb_test -- send_gdb a command to gdb and test the result.
#             Takes three parameters.
#             Parameters:
#                First one is the command to execute.  If this is the null string
#                  then no command is sent.
#                Second one is the pattern to match for a PASS, and must NOT include
#                  the \r\n sequence immediately before the gdb prompt.
#                Third one is an optional message to be printed. If this
#                  a null string "", then the pass/fail messages use the command
#                  string as the message.
#             Returns:
#                1 if the test failed,
#                0 if the test passes,
#               -1 if there was an internal error.
#
proc gdb_test { args } {
    global verbose
    global gdb_prompt
    global GDB
    upvar timeout timeout

    if [llength $args]>2 then {
        set message [lindex $args 2]
    } else {
        set message [lindex $args 0]
    }
    set command [lindex $args 0]
    set pattern [lindex $args 1]

    if [llength $args]==5 {
        set question_string [lindex $args 3];
        set response_string [lindex $args 4];
    } else {
        set question_string "^FOOBAR$"
    }

    if $verbose>2 then {
        send_user "Sending \"$command\" to gdb\n"
        send_user "Looking to match \"$pattern\"\n"
        send_user "Message is \"$message\"\n"
    }

    set result -1
    if ![string match $command ""] {
        if { [send_gdb "$command\n"] != "" } {
            global suppress_flag;

            if { ! $suppress_flag } {
                perror "Couldn't send $command to GDB.";
            }
            fail "$message";
            return $result;
        }
    }

    if [info exists timeout] {
        set tmt $timeout;
    } else {
        global timeout;
        if [info exists timeout] {
            set tmt $timeout;
        } else {
            set tmt 60;
        }
    }
    gdb_expect $tmt {
         -re "Ending remote debugging.*$gdb_prompt$" {
            if ![isnative] then {
                warning "Can`t communicate to remote target."
            }
            gdb_exit
            gdb_start
            set result -1
        }
         -re "\[\r\n\]*($pattern)\[\r\n\]+$gdb_prompt $" {
            if ![string match "" $message] then {
                pass "$message"
            }
            set result 0
        }
         -re "(${question_string})$" {
            send_gdb "$response_string\n";
            exp_continue;
        }
         -re "Undefined command:.*$gdb_prompt" {
            perror "Undefined command \"$command\"."
            set result 1
        }
         -re "Ambiguous command.*$gdb_prompt $" {
            perror "\"$command\" is not a unique command name."
            set result 1
        }
         -re "Program exited with code \[0-9\]+.*$gdb_prompt $" {
            if ![string match "" $message] then {
                set errmsg "$message: the program exited"
            } else {
                set errmsg "$command: the program exited"
            }
            fail "$errmsg"
            return -1
        }
         -re "The program is not being run.*$gdb_prompt $" {
            if ![string match "" $message] then {
                set errmsg "$message: the program is no longer running"
            } else {
                set errmsg "$command: the program is no longer running"
            }
            fail "$errmsg"
            return -1
        }
         -re ".*$gdb_prompt $" {
            if ![string match "" $message] then {
                fail "$message"
            }
            set result 1
        }
         "<return>" {
            send_gdb "\n"
            perror "Window too small."
        }
         -re "\\(y or n\\) " {
            send_gdb "n\n"
            perror "Got interactive prompt."
        }
         eof {
             perror "Process no longer exists"
             if { $message != "" } {
                 fail "$message"
             }
             return -1
        }
         full_buffer {
            perror "internal buffer is full."
        }
        timeout {
            if ![string match "" $message] then {
                fail "$message (timeout)"
            }
            set result 1
        }
    }
    return $result
}
\f
# Test that a command gives an error.  For pass or fail, return
# a 1 to indicate that more tests can proceed.  However a timeout
# is a serious error, generates a special fail message, and causes
# a 0 to be returned to indicate that more tests are likely to fail
# as well.

proc test_print_reject { args } {
    global gdb_prompt
    global verbose

    if [llength $args]==2 then {
        set expectthis [lindex $args 1]
    } else {
        set expectthis "should never match this bogus string"
    }
    set sendthis [lindex $args 0]
    if $verbose>2 then {
        send_user "Sending \"$sendthis\" to gdb\n"
        send_user "Looking to match \"$expectthis\"\n"
    }
    send_gdb "$sendthis\n"
    #FIXME: Should add timeout as parameter.
    gdb_expect {
        -re "A .* in expression.*\\.*$gdb_prompt $" {
            pass "reject $sendthis"
            return 1
        }
        -re "Invalid syntax in expression.*$gdb_prompt $" {
            pass "reject $sendthis"
            return 1
        }
        -re "Junk after end of expression.*$gdb_prompt $" {
            pass "reject $sendthis"
            return 1
        }
        -re "Invalid number.*$gdb_prompt $" {
            pass "reject $sendthis"
            return 1
        }
        -re "Invalid character constant.*$gdb_prompt $" {
            pass "reject $sendthis"
            return 1
        }
        -re "No symbol table is loaded.*$gdb_prompt $" {
            pass "reject $sendthis"
            return 1
        }
        -re "No symbol .* in current context.*$gdb_prompt $" {
            pass "reject $sendthis"
            return 1
        }
        -re "$expectthis.*$gdb_prompt $" {
            pass "reject $sendthis"
            return 1
        }
        -re ".*$gdb_prompt $" {
            fail "reject $sendthis"
            return 1
        }
        default {
            fail "reject $sendthis (eof or timeout)"
            return 0
        }
    }
}
\f
# Given an input string, adds backslashes as needed to create a
# regexp that will match the string.

proc string_to_regexp {str} {
    set result $str
    regsub -all {[]*+.|()^$\[]} $str {\\&} result
    return $result
}

# Same as gdb_test, but the second parameter is not a regexp,
# but a string that must match exactly.

proc gdb_test_exact { args } {
    upvar timeout timeout

    set command [lindex $args 0]

    # This applies a special meaning to a null string pattern.  Without
    # this, "$pattern\r\n$gdb_prompt $" will match anything, including error
    # messages from commands that should have no output except a new
    # prompt.  With this, only results of a null string will match a null
    # string pattern.

    set pattern [lindex $args 1]
    if [string match $pattern ""] {
        set pattern [string_to_regexp [lindex $args 0]]
    } else {
        set pattern [string_to_regexp [lindex $args 1]]
    }

    # It is most natural to write the pattern argument with only
    # embedded \n's, especially if you are trying to avoid Tcl quoting
    # problems.  But gdb_expect really wants to see \r\n in patterns.  So
    # transform the pattern here.  First transform \r\n back to \n, in
    # case some users of gdb_test_exact already do the right thing.
    regsub -all "\r\n" $pattern "\n" pattern
    regsub -all "\n" $pattern "\r\n" pattern
    if [llength $args]==3 then {
        set message [lindex $args 2]
    } else {
        set message $command
    }

    return [gdb_test $command $pattern $message]
}
\f
proc gdb_reinitialize_dir { subdir } {
    global gdb_prompt

    if [is_remote host] {
        return "";
    }
    send_gdb "dir\n"
    gdb_expect 60 {
        -re "Reinitialize source path to empty.*y or n. " {
            send_gdb "y\n"
            gdb_expect 60 {
                -re "Source directories searched.*$gdb_prompt $" {
                    send_gdb "dir $subdir\n"
                    gdb_expect 60 {
                        -re "Source directories searched.*$gdb_prompt $" {
                            verbose "Dir set to $subdir"
                        }
                        -re "$gdb_prompt $" {
                            perror "Dir \"$subdir\" failed."
                        }
                    }
                }
                -re "$gdb_prompt $" {
                    perror "Dir \"$subdir\" failed."
                }
            }
        }
        -re "$gdb_prompt $" {
            perror "Dir \"$subdir\" failed."
        }
    }
}

#
# gdb_exit -- exit the GDB, killing the target program if necessary
#
proc default_gdb_exit {} {
    global GDB
    global GDBFLAGS
    global verbose
    global gdb_spawn_id;

    gdb_stop_suppressing_tests;

    if ![info exists gdb_spawn_id] {
        return;
    }

    verbose "Quitting $GDB $GDBFLAGS"

    if { [is_remote host] && [board_info host exists fileid] } {
        send_gdb "quit\n";
        gdb_expect 10 {
            -re "and kill it.*y or n. " {
                send_gdb "y\n";
                exp_continue;
            }
            -re "DOSEXIT code" { }
            default { }
        }
    }

    remote_close host;
    unset gdb_spawn_id
}

#
# load a file into the debugger.
# return a -1 if anything goes wrong.
#
proc gdb_file_cmd { arg } {
    global verbose
    global loadpath
    global loadfile
    global GDB
    global gdb_prompt
    upvar timeout timeout

    if [is_remote host] {
        set arg [remote_download host $arg];
        if { $arg == "" } {
            error "download failed"
            return -1;
        }
    }

    send_gdb "file $arg\n"
    gdb_expect 120 {
        -re "Reading symbols from.*done.*$gdb_prompt $" {
            verbose "\t\tLoaded $arg into the $GDB"
            return 0
        }
        -re "has no symbol-table.*$gdb_prompt $" {
            perror "$arg wasn't compiled with \"-g\""
            return -1
        }
        -re "A program is being debugged already.*Kill it.*y or n. $" {
            send_gdb "y\n"
                verbose "\t\tKilling previous program being debugged"
            exp_continue
        }
        -re "Load new symbol table from \".*\".*y or n. $" {
            send_gdb "y\n"
            gdb_expect 120 {
                -re "Reading symbols from.*done.*$gdb_prompt $" {
                    verbose "\t\tLoaded $arg with new symbol table into $GDB"
                    return 0
                }
                timeout {
                    perror "(timeout) Couldn't load $arg, other program already loaded."
                    return -1
                }
            }
        }
        -re "No such file or directory.*$gdb_prompt $" {
            perror "($arg) No such file or directory\n"
            return -1
        }
        -re "$gdb_prompt $" {
            perror "couldn't load $arg into $GDB."
            return -1
            }
        timeout {
            perror "couldn't load $arg into $GDB (timed out)."
            return -1
        }
        eof {
            # This is an attempt to detect a core dump, but seems not to
            # work.  Perhaps we need to match .* followed by eof, in which
            # gdb_expect does not seem to have a way to do that.
            perror "couldn't load $arg into $GDB (end of file)."
            return -1
        }
    }
}

#
# start gdb -- start gdb running, default procedure
#
# When running over NFS, particularly if running many simultaneous
# tests on different hosts all using the same server, things can
# get really slow.  Give gdb at least 3 minutes to start up.
#
proc default_gdb_start { } {
    global verbose
    global GDB
    global GDBFLAGS
    global gdb_prompt
    global timeout
    global gdb_spawn_id;

    gdb_stop_suppressing_tests;

    verbose "Spawning $GDB -nw $GDBFLAGS"

    if [info exists gdb_spawn_id] {
        return 0;
    }

    if ![is_remote host] {
        if { [which $GDB] == 0 } then {
            perror "$GDB does not exist."
            exit 1
        }
    }
    set res [remote_spawn host "$GDB -nw $GDBFLAGS [host_info gdb_opts]"];
    if { $res < 0 || $res == "" } {
        perror "Spawning $GDB failed."
        return 1;
    }
    gdb_expect 360 {
        -re "\[\r\n\]$gdb_prompt $" {
            verbose "GDB initialized."
        }
        -re "$gdb_prompt $"     {
            perror "GDB never initialized."
            return -1
        }
        timeout {
            perror "(timeout) GDB never initialized after 10 seconds."
            remote_close host;
            return -1
        }
    }
    set gdb_spawn_id -1;
    # force the height to "unlimited", so no pagers get used

    send_gdb "set height 0\n"
    gdb_expect 10 {
        -re "$gdb_prompt $" { 
            verbose "Setting height to 0." 2
        }
        timeout {
            warning "Couldn't set the height to 0"
        }
    }
    # force the width to "unlimited", so no wraparound occurs
    send_gdb "set width 0\n"
    gdb_expect 10 {
        -re "$gdb_prompt $" {
            verbose "Setting width to 0." 2
        }
        timeout {
            warning "Couldn't set the width to 0."
        }
    }
    return 0;
}

# * For crosses, the CHILL runtime doesn't build because it can't find
# setjmp.h, stdio.h, etc.
# * For AIX (as of 16 Mar 95), (a) there is no language code for
# CHILL in output_epilog in gcc/config/rs6000/rs6000.c, (b) collect2
# does not get along with AIX's too-clever linker.
# * On Irix5, there is a bug whereby set of bool, etc., don't get
# TYPE_LOW_BOUND for the bool right because force_to_range_type doesn't
# work with stub types.
# Lots of things seem to fail on the PA, and since it's not a supported
# chill target at the moment, don't run the chill tests.

proc skip_chill_tests {} {
    if ![info exists do_chill_tests] {
        return 1;
    }
    eval set skip_chill [expr ![isnative] || [istarget "*-*-aix*"] || [istarget "*-*-irix5*"] || [istarget "*-*-irix6*"] || [istarget "alpha-*-osf*"] || [istarget "hppa*-*-*"]]
    verbose "Skip chill tests is $skip_chill"
    return $skip_chill
}

proc get_compiler_info {binfile} {
    # Create and source the file that provides information about the compiler
    # used to compile the test case.
    global srcdir
    global subdir
    # These two come from compiler.c.
    global signed_keyword_not_used
    global gcc_compiled

    if { [gdb_compile "${srcdir}/${subdir}/compiler.c" "${binfile}.ci" preprocess {}] != "" } {
        perror "Couldn't make ${binfile}.ci file"
        return 1;
    }
    source ${binfile}.ci
    return 0;
}

proc gdb_compile {source dest type options} {
    global GDB_TESTCASE_OPTIONS;

    if [target_info exists gdb_stub] {
        set options2 { "additional_flags=-Dusestubs" }
        lappend options "libs=[target_info gdb_stub]";
        set options [concat $options2 $options]
    }
    if [info exists GDB_TESTCASE_OPTIONS] {
        lappend options "additional_flags=$GDB_TESTCASE_OPTIONS";
    }
    verbose "options are $options"
    verbose "source is $source $dest $type $options"
    set result [target_compile $source $dest $type $options];
    regsub "\[\r\n\]*$" "$result" "" result;
    regsub "^\[\r\n\]*" "$result" "" result;
    if { $result != "" } {
        clone_output "gdb compile failed, $result"
    }
    return $result;
}

proc send_gdb { string } {
    global suppress_flag;
    if { $suppress_flag } {
        return "suppressed";
    }
    return [remote_send host "$string"];
}

#
#

proc gdb_expect { args } {
    if { [llength $args] == 2  && [lindex $args 0] != "-re" } {
        set gtimeout [lindex $args 0];
        set expcode [list [lindex $args 1]];
    } else {
        upvar timeout timeout;

        set expcode $args;
        if [target_info exists gdb,timeout] {
            if [info exists timeout] {
                if { $timeout < [target_info gdb,timeout] } {
                    set gtimeout [target_info gdb,timeout];
                } else {
                    set gtimeout $timeout;
                }
            } else {
                set gtimeout [target_info gdb,timeout];
            }
        }

        if ![info exists gtimeout] {
            global timeout;
            if [info exists timeout] {
                set gtimeout $timeout;
            } else {
                # Eeeeew.
                set gtimeout 60;
            }
        }
    }
    set code [catch {uplevel remote_expect host $gtimeout $expcode} string];

    if {$code == 1} {
        global errorInfo errorCode;

        return -code error -errorinfo $errorInfo -errorcode $errorCode $string
    } elseif {$code == 2} {
        return -code return $string
    } elseif {$code == 3} {
        return
    } elseif {$code > 4} {
        return -code $code $string
    }
}

proc gdb_suppress_entire_file { reason } {
    global suppress_flag;

    warning "$reason\n";
    set suppress_flag -1;
}

#
# Set suppress_flag, which will cause all subsequent calls to send_gdb and
# gdb_expect to fail immediately (until the next call to 
# gdb_stop_suppressing_tests).
#
proc gdb_suppress_tests { args } {
    global suppress_flag;

    incr suppress_flag;

    if { $suppress_flag == 1 } {
        if { [llength $args] > 0 } {
            warning "[lindex $args 0]\n";
        } else {
            warning "Because of previous failure, all subsequent tests in this group will automatically fail.\n";
        }
    }
}

#
# Clear suppress_flag.
#
proc gdb_stop_suppressing_tests { } {
    global suppress_flag;

    if [info exists suppress_flag] {
        if { $suppress_flag > 0 } {
            set suppress_flag 0;
            clone_output "Tests restarted.\n";
        }
    } else {
        set suppress_flag 0;
    }
}

proc gdb_clear_suppressed { } {
    global suppress_flag;

    set suppress_flag 0;
}

proc gdb_start { } {
    default_gdb_start
}

proc gdb_exit { } {
    catch default_gdb_exit
}

#
# gdb_load -- load a file into the debugger.
#             return a -1 if anything goes wrong.
#
proc gdb_load { arg } {
    return [gdb_file_cmd $arg]
}

proc gdb_continue { function } {
    global decimal

    return [gdb_test "continue" ".*Breakpoint $decimal, $function .*" "continue to $function"];
}

proc default_gdb_init { args } {
    gdb_clear_suppressed;

    # Uh, this is lame. Really, really, really lame. But there's this *one*
    # testcase that will fail in random places if we don't increase this.
    match_max -d 20000

    # We want to add the name of the TCL testcase to the PASS/FAIL messages.
    if { [llength $args] > 0 } {
        global pf_prefix

        set file [lindex $args 0];

        set pf_prefix "[file tail [file dirname $file]]/[file tail $file]:";
    }
    global gdb_prompt;
    if [target_info exists gdb_prompt] {
        set gdb_prompt [target_info gdb_prompt];
    } else {
        set gdb_prompt "\\(gdb\\)"
    }
}

proc gdb_init { args } {
    return [eval default_gdb_init $args];
}

proc gdb_finish { } {
    gdb_exit;
}

global debug_format

# Run the gdb command "info source" and extract the debugging format information
# from the output and save it in debug_format.

proc get_debug_format { } {
    global gdb_prompt
    global verbose
    global expect_out
    global debug_format

    set debug_format "unknown"
    send_gdb "info source\n"
    gdb_expect 10 {
        -re "Compiled with (.*) debugging format.\r\n$gdb_prompt $" {
            set debug_format $expect_out(1,string)
            verbose "debug format is $debug_format"
            return 1;
        }
        -re "No current source file.\r\n$gdb_prompt $" {
            perror "get_debug_format used when no current source file"
            return 0;
        }
        -re "$gdb_prompt $" {
            warning "couldn't check debug format (no valid response)."
            return 1;
        }
        timeout {
            warning "couldn't check debug format (timed out)."
            return 1;
        }
    }
}

# Like setup_xfail, but takes the name of a debug format (DWARF 1, COFF, stabs, etc).
# If that format matches the format that the current test was compiled with, then
# the next test is expected to fail for any target.  Returns 1 if the next test or
# set of tests is expected to fail, 0 otherwise (or if it is unknown).  Must
# have previously called get_debug_format.

proc setup_xfail_format { format } {
    global debug_format

    if [string match $debug_format $format] then {
        setup_xfail "*-*-*"
        return 1;
    }
    return 0
}    

proc gdb_step_for_stub { } {
    global gdb_prompt;

    if [target_info exists gdb_stub_step_command] {
        set command [target_info gdb_stub_step_command];
    } else {
        set command "step";
    }
    send_gdb "${command}\n";
    set tries 0;
    gdb_expect 60 {
        -re "(main.* at |.*in .*start).*$gdb_prompt" {
            return;
        }
        -re "libgloss/\[a-z\]*\[0-9\]*/stub.c" {
            send_gdb "where\n";
            gdb_expect {
                -re "main\[^\r\n\]*at \(\[^:]+\):\(\[0-9\]+\)" {
                    set file $expect_out(1,string);
                    set linenum [expr $expect_out(2,string) + 1];
                    set breakplace "${file}:${linenum}";
                }
                default {}
            }
            send_gdb "break ${breakplace}\n";
            gdb_expect 60 {
                -re "Breakpoint (\[0-9\]+) at.*$gdb_prompt" {
                    set breakpoint $expect_out(1,string);
                }
                -re "Breakpoint (\[0-9\]+): file.*$gdb_prompt" {
                    set breakpoint $expect_out(1,string);
                }
                default {}
            }
            send_gdb "continue\n";
            gdb_expect 60 {
                -re "Breakpoint ${breakpoint},.*$gdb_prompt" {
                    gdb_test "delete $breakpoint" ".*" "";
                    return;
                }
                default {}
            }
        }
        -re ".*$gdb_prompt" {
            incr tries;
            if { $tries == 5 } {
                fail "stepping out of breakpoint function";
                return;
            }
            send_gdb "${command}\n";
            exp_continue;
        }
        default {
            fail "stepping out of breakpoint function";
            return;
        }
    }
}