From 48e9cc84058771da089a2e8e652f70ac20a8fac0 Mon Sep 17 00:00:00 2001 From: Philippe Waroquiers Date: Sat, 23 May 2020 14:54:31 +0200 Subject: [PATCH] Ensure 'exec-file has changed' check has priority over 'exec-file-mismatch' check Following the implementation of exec-file-mismatch based on build-id, an attach to a process that runs a modified exec-file was triggering the exec-file-mismatch handling, giving a warning such as: warning: Mismatch between current exec-file /bd/home/philippe/gdb/git/build_termours/gdb/testsuite/outputs/gdb.base/attach/attach and automatically determined exec-file /bd/home/philippe/gdb/git/build_termours/gdb/testsuite/outputs/gdb.base/attach/attach exec-file-mismatch handling is currently "ask" as the build-ids differ when an exec-file is recompiled. This patch ensures that the exec-file-mismatch check is done with an up to date build-id. With this, exec-file-mismatch check will only trigger when the PID file really differs from the (build-id refreshed) current exec-file. Note that the additional check does not (yet) reload the symbols if the exec-file is changed: this reload will happen later if needed. gdb/ChangeLog 2020-06-21 Philippe Waroquiers * exec.c (validate_exec_file): Ensure the build-id is up to date by calling reopen_exec_file (that checks file timestamp to decide to re-read the file). gdb/testsuite/ChangeLog 2020-06-21 Philippe Waroquiers * gdb.base/attach.exp: Test priority of 'exec-file' changed over 'exec-file-mismatch'. * gdb.base/attach.c: Mark should_exit volatile. * gdb.base/attach2.c: Likewise. Add a comment explaining why the sleep cannot be big. * gdb.base/attach3.c: New file. --- gdb/ChangeLog | 6 ++++ gdb/exec.c | 8 +++++ gdb/testsuite/ChangeLog | 9 ++++++ gdb/testsuite/gdb.base/attach.c | 2 +- gdb/testsuite/gdb.base/attach.exp | 54 +++++++++++++++++++++++++++++-- gdb/testsuite/gdb.base/attach2.c | 4 ++- gdb/testsuite/gdb.base/attach3.c | 25 ++++++++++++++ 7 files changed, 104 insertions(+), 4 deletions(-) create mode 100644 gdb/testsuite/gdb.base/attach3.c diff --git a/gdb/ChangeLog b/gdb/ChangeLog index ff1fd7f4056..d03aae63ce8 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,9 @@ +2020-06-21 Philippe Waroquiers + + * exec.c (validate_exec_file): Ensure the build-id is up to + date by calling reopen_exec_file (that checks file timestamp + to decide to re-read the file). + 2020-06-18 Pedro Alves PR gdb/25412 diff --git a/gdb/exec.c b/gdb/exec.c index ee13c5e027e..fa770c6f020 100644 --- a/gdb/exec.c +++ b/gdb/exec.c @@ -256,6 +256,14 @@ validate_exec_file (int from_tty) /* Try validating via build-id, if available. This is the most reliable check. */ + + /* In case current_exec_file was changed, reopen_exec_file ensures + an up to date build_id (will do nothing if the file timestamp + did not change). If exec file changed, reopen_exec_file has + allocated another file name, so get_exec_file again. */ + reopen_exec_file (); + current_exec_file = get_exec_file (0); + const bfd_build_id *exec_file_build_id = build_id_bfd_get (exec_bfd); if (exec_file_build_id != nullptr) { diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 713ec37cdf2..5d64783df5d 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,12 @@ +2020-06-21 Philippe Waroquiers + + * gdb.base/attach.exp: Test priority of 'exec-file' changed + over 'exec-file-mismatch'. + * gdb.base/attach.c: Mark should_exit volatile. + * gdb.base/attach2.c: Likewise. Add a comment explaining + why the sleep cannot be big. + * gdb.base/attach3.c: New file. + 2020-06-20 Sandra Loosemore * gdb.mi/mi-sym-info.exp: Adjust filename patterns to make directory diff --git a/gdb/testsuite/gdb.base/attach.c b/gdb/testsuite/gdb.base/attach.c index 2e87f9b7104..b3c54984012 100644 --- a/gdb/testsuite/gdb.base/attach.c +++ b/gdb/testsuite/gdb.base/attach.c @@ -8,7 +8,7 @@ #include int bidule = 0; -int should_exit = 0; +volatile int should_exit = 0; int main () { diff --git a/gdb/testsuite/gdb.base/attach.exp b/gdb/testsuite/gdb.base/attach.exp index 32f72e2a9a2..ab2d3185762 100644 --- a/gdb/testsuite/gdb.base/attach.exp +++ b/gdb/testsuite/gdb.base/attach.exp @@ -17,12 +17,13 @@ if {![can_spawn_for_attach]} { return 0 } -standard_testfile attach.c attach2.c +standard_testfile attach.c attach2.c attach3.c set binfile2 ${binfile}2 +set binfile3 ${binfile}3 set escapedbinfile [string_to_regexp $binfile] #execute_anywhere "rm -f ${binfile} ${binfile2}" -remote_exec build "rm -f ${binfile} ${binfile2}" +remote_exec build "rm -f ${binfile} ${binfile2} ${binfile3}" # For debugging this test # #log_user 1 @@ -41,6 +42,13 @@ if { [gdb_compile "${srcdir}/${subdir}/${srcfile2}" "${binfile2}" executable {d return -1 } +# Build the third file, used to check attach when the exec-file has changed. + +if { [gdb_compile "${srcdir}/${subdir}/${srcfile3}" "${binfile3}" executable {debug}] != "" } { + untested "failed to compile attach exec-file changed test" + return -1 +} + if [get_compiler_info] { return -1 } @@ -515,6 +523,7 @@ proc_with_prefix do_attach_exec_mismatch_handling_tests {} { global gdb_prompt global binfile global binfile2 + global binfile3 clean_restart $binfile @@ -577,10 +586,51 @@ proc_with_prefix do_attach_exec_mismatch_handling_tests {} { # Detach the process. gdb_test "detach" "Detaching from program: .* detached\\\]" "$test detach attach" + # Test that the 'exec-file' changed is checked before exec-file-mismatch. + set test "mismatch exec-file changed has priority" + gdb_test_no_output "set exec-file-mismatch ask" + gdb_test_multiple "attach $testpid" "$test attach1 again, initial exec-file" { + -re "Attaching to program.*exec-file-mismatch handling is currently \"ask\".*Load new symbol table from .*attach\".*\(y or n\)" { + gdb_test "y" "Reading symbols from .*attach.*" $gdb_test_name + } + } + + + gdb_test "detach" "Detaching from program: .* detached\\\]" "$test detach attach initial exec-file" + + # Change the exec-file and attach to a new process using the changed file. + remote_exec build "mv ${binfile} ${binfile}.initial" + remote_exec build "mv ${binfile3} ${binfile}" + # Ensure GDB detects ${binfile} has changed when checking timestamp. + sleep 1 + remote_exec build "touch ${binfile}" + set test_spawn_id3 [spawn_wait_for_attach $binfile] + set testpid3 [spawn_id_get_pid $test_spawn_id3] + + gdb_test "attach $testpid3" "Attaching to program.*attach' has changed; re-reading symbols.*" \ + "$test attach1 again, after changing exec-file" + gdb_test "detach" "Detaching from program: .* detached\\\]" "$test detach after attach changed exec-file" + + # Now, test the situation when current exec-file has changed + # and we attach to a pid using another file. + # Ensure GDB detects ${binfile} has changed when checking timestamp. + sleep 1 + remote_exec build "touch ${binfile}" + + gdb_test_multiple "attach $testpid2" "$test attach2" { + -re "Attaching to program.*exec-file-mismatch handling is currently \"ask\".*Load new symbol table from .*attach2\".*\(y or n\)" { + gdb_test "y" "Reading symbols from .*attach2.*" $gdb_test_name + } + } + + # Restore initial build situation. + remote_exec build "mv ${binfile} ${binfile3}" + remote_exec build "mv ${binfile}.initial ${binfile}" # Don't leave a process around kill_wait_spawned_process $test_spawn_id kill_wait_spawned_process $test_spawn_id2 + kill_wait_spawned_process $test_spawn_id3 } do_attach_tests diff --git a/gdb/testsuite/gdb.base/attach2.c b/gdb/testsuite/gdb.base/attach2.c index 44d37258fbc..d070d933b08 100644 --- a/gdb/testsuite/gdb.base/attach2.c +++ b/gdb/testsuite/gdb.base/attach2.c @@ -9,12 +9,14 @@ #include float bidule = 0.0; -int should_exit = 0; +volatile int should_exit = 0; int main () { int local_i = 0; + /* Cannot sleep a very long time, as attach.exp assumes the + process will exit before the standard GDB timeout. */ sleep( 10 ); /* System call causes register fetch to fail */ /* This is a known HPUX "feature" */ while (! should_exit) diff --git a/gdb/testsuite/gdb.base/attach3.c b/gdb/testsuite/gdb.base/attach3.c new file mode 100644 index 00000000000..09a6d886df9 --- /dev/null +++ b/gdb/testsuite/gdb.base/attach3.c @@ -0,0 +1,25 @@ +/* This program is intended to be started outside of gdb, and then + attached to by gdb. Thus, it simply spins in a loop. The loop + is exited when & if the variable 'should_exit' is non-zero. (It + is initialized to zero in this program, so the loop will never + exit unless/until gdb sets the variable to non-zero.) + */ +#include +#include +#include + +double bidule = 0.0; +volatile int should_exit = 0; + +int main () +{ + int local_i = 0; + + sleep( 60 ); /* System call causes register fetch to fail */ + /* This is a known HPUX "feature" */ + while (! should_exit) + { + local_i++; + } + return (0); +} -- 2.30.2