xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/testsuite/gdb.threads/pending-step.exp (revision 8b657b0747480f8989760d71343d6dd33f8d4cf9)
1# Copyright (C) 2009-2023 Free Software Foundation, Inc.
2
3# This program is free software; you can redistribute it and/or modify
4# it under the terms of the GNU General Public License as published by
5# the Free Software Foundation; either version 3 of the License, or
6# (at your option) any later version.
7#
8# This program is distributed in the hope that it will be useful,
9# but WITHOUT ANY WARRANTY; without even the implied warranty of
10# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11# GNU General Public License for more details.
12#
13# You should have received a copy of the GNU General Public License
14# along with this program.  If not, see <http://www.gnu.org/licenses/>.
15
16# Test that a resume cancels a previously unfinished or unreported
17# single-step correctly.
18#
19# The test consists of several threads all running the same loop.
20# There is a breakpoint set in the loop, hence all threads may hit it.
21# The test then issues several "next" commands in a loop.
22#
23# scheduler-locking must be set to the default of "off".
24#
25# Here's what would happen in gdbserver:
26#
27# 1) We issue a "continue", and wait until a thread hits the
28#    breakpoint.  Could be any thread, but assume thread 1 hits it.
29#
30# 2) We issue a "next" --- this single-steps thread 1, and resumes all
31#    other threads.
32#
33# 3) thread 2, due to scheduler-locking off, hits the breakpoint.
34#    gdbserver stops all other threads by sending them SIGSTOPs.
35#
36# 4) While being stopped in step 3, thread 1 reports a SIGTRAP, that
37#    corresponds to the finished single-step of step 2.  gdbserver
38#    leaves the SIGTRAP pending to report later.
39#
40# 5) We issue another "next" --- this requests thread 2 to
41#    single-step, and all other threads to continue, including thread
42#    1.  Before resuming any thread, gdbserver notices that it
43#    remembers from step 4 a pending SIGTRAP to report for thread 1,
44#    so reports it now.
45#
46# 6) From GDB's perpective, this SIGTRAP can't represent a finished
47#    single-step, since thread 1 was not single-stepping (it was
48#    continued in step 5).  Neither does this SIGTRAP correspond to a
49#    breakpoint hit.  GDB reports to the user a spurious SIGTRAP.
50
51standard_testfile
52
53if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable debug] != "" } {
54    return -1
55}
56
57clean_restart ${binfile}
58
59if {![runto_main]} {
60    return 0
61}
62
63gdb_breakpoint [gdb_get_line_number "insert breakpoint here"]
64gdb_continue_to_breakpoint "continue to first breakpoint hit"
65
66set test "next in multiple threads with breakpoints"
67set iterations 20
68set ok 0
69for {set i 0} {$i < $iterations} {incr i} {
70    set ok 0
71    gdb_test_multiple "next" "$test" {
72	-re " received signal SIGTRAP.*$gdb_prompt $" {
73	    fail "$test (spurious SIGTRAP)"
74	}
75	-re "$gdb_prompt $" {
76	    set ok 1
77	}
78    }
79
80    if { $ok == 0 } {
81	break
82    }
83}
84
85if { $ok  } {
86    pass "$test"
87}
88