Index: gdb-7.4.50.20120602/gdb/linux-nat.c =================================================================== --- gdb-7.4.50.20120602.orig/gdb/linux-nat.c 2012-06-02 20:51:58.000000000 +0200 +++ gdb-7.4.50.20120602/gdb/linux-nat.c 2012-06-02 20:54:30.127529159 +0200 @@ -180,6 +180,9 @@ blocked. */ static struct target_ops *linux_ops; static struct target_ops linux_ops_saved; +/* PID of the inferior stopped by SIGSTOP before attaching (or zero). */ +static pid_t pid_was_stopped; + /* The method to call, if any, when a new thread is attached. */ static void (*linux_nat_new_thread) (struct lwp_info *); @@ -909,7 +912,14 @@ holding the child stopped. Try \"set de parent_inf->waiting_for_vfork_done = 0; } else if (detach_fork) - target_detach (NULL, 0); + { + /* We should check PID_WAS_STOPPED and detach it stopped accordingly. + In this point of code it cannot be 1 as we would not get FORK + executed without CONTINUE first which resets PID_WAS_STOPPED. + We would have to first TARGET_STOP and WAITPID it as with running + inferior PTRACE_DETACH, SIGSTOP will ignore the signal. */ + target_detach (NULL, 0); + } /* Note that the detach above makes PARENT_INF dangling. */ @@ -1377,6 +1387,7 @@ linux_nat_post_attach_wait (ptid_t ptid, if (debug_linux_nat) fprintf_unfiltered (gdb_stdlog, "LNPAW: Attaching to a stopped process\n"); + pid_was_stopped = GET_PID (ptid); /* The process is definitely stopped. It is in a job control stop, unless the kernel predates the TASK_STOPPED / @@ -1805,6 +1816,9 @@ get_pending_status (struct lwp_info *lp, gdb_signal_to_string (signo)); } + if (*status == 0 && GET_PID (lp->ptid) == pid_was_stopped) + *status = W_STOPCODE (SIGSTOP); + return 0; } @@ -1918,6 +1932,8 @@ linux_nat_detach (struct target_ops *ops } else linux_ops->to_detach (ops, args, from_tty); + + pid_was_stopped = 0; } /* Resume LP. */ @@ -2083,6 +2099,14 @@ linux_nat_resume (struct target_ops *ops resume_callback. */ lp->stopped = 0; + /* At this point, we are going to resume the inferior and if we + have attached to a stopped process, we no longer should leave + it as stopped if the user detaches. PTID variable has PID set to LWP + while we need to check the real PID here. */ + + if (!step && lp && pid_was_stopped == GET_PID (lp->ptid)) + pid_was_stopped = 0; + if (resume_many) iterate_over_lwps (ptid, resume_callback, NULL); @@ -4132,6 +4156,8 @@ linux_nat_mourn_inferior (struct target_ there are other viable forks to debug. Delete the exiting one and context-switch to the first available. */ linux_fork_mourn_inferior (); + + pid_was_stopped = 0; } /* Convert a native/host siginfo object, into/from the siginfo in the Index: gdb-7.4.50.20120602/gdb/testsuite/gdb.threads/attach-stopped.exp =================================================================== --- gdb-7.4.50.20120602.orig/gdb/testsuite/gdb.threads/attach-stopped.exp 2012-01-04 09:27:55.000000000 +0100 +++ gdb-7.4.50.20120602/gdb/testsuite/gdb.threads/attach-stopped.exp 2012-06-02 20:52:08.893505403 +0200 @@ -63,7 +63,65 @@ proc corefunc { threadtype } { gdb_reinitialize_dir $srcdir/$subdir gdb_load ${binfile} - # Verify that we can attach to the stopped process. + # Verify that we can attach to the process by first giving its + # executable name via the file command, and using attach with the + # process ID. + + set test "$threadtype: set file, before attach1 to stopped process" + gdb_test_multiple "file $binfile" "$test" { + -re "Load new symbol table from.*y or n. $" { + gdb_test "y" "Reading symbols from $escapedbinfile\.\.\.*done." \ + "$test (re-read)" + } + -re "Reading symbols from $escapedbinfile\.\.\.*done.*$gdb_prompt $" { + pass "$test" + } + } + + set test "$threadtype: attach1 to stopped, after setting file" + gdb_test_multiple "attach $testpid" "$test" { + -re "Attaching to program.*`?$escapedbinfile'?, process $testpid.*$gdb_prompt $" { + pass "$test" + } + } + + # ".*sleep.*clone.*" would fail on s390x as bt stops at START_THREAD there. + if {[string equal $threadtype threaded]} { + gdb_test "thread apply all bt" ".*sleep.*start_thread.*" "$threadtype: attach1 to stopped bt" + } else { + gdb_test "bt" ".*sleep.*main.*" "$threadtype: attach1 to stopped bt" + } + + # Exit and detach the process. + + gdb_exit + + # Avoid some race: + sleep 2 + + if [catch {open /proc/${testpid}/status r} fileid] { + set line2 "NOTFOUND" + } else { + gets $fileid line1; + gets $fileid line2; + close $fileid; + } + + set test "$threadtype: attach1, exit leaves process stopped" + if {[string match "*(stopped)*" $line2]} { + pass $test + } else { + fail $test + } + + # At this point, the process should still be stopped + + gdb_start + gdb_reinitialize_dir $srcdir/$subdir + gdb_load ${binfile} + + # Verify that we can attach to the process just by giving the + # process ID. set test "$threadtype: attach2 to stopped, after setting file" gdb_test_multiple "attach $testpid" "$test" {