Re: [PATCH v2] New testcase for PR tui/25126 (staled source cache)

Luis Machado
2020-02-10T19:33:16Z

I think you attached v1 again, no?

On 2/10/20 4:09 PM, Sergio Durigan Junior wrote:
> Changes since v1:
>
> - Fix typo.
> - Improve testcase description.
> - Use 'gdb_assert'.
> - Improve description of "sleep 1" statement.
>
>
> I'm dealing with a Fedora GDB bug that is related to PR tui/25126, and
> I thought I'd write a specific testcase for it because I couldn't find
> one.
>
> The idea is to get the simple reproducer from the bug and tweak the
> testcase around it. This one was a bit hard because, since we need to
> modify the source file and recompile it, it involved a bit of TCL-foo
> to do things. Also for this reason, I'm only enabling the test for
> native boards.
>
> I tested this with an upstream GDB and made sure everything is
> passing. I also tested with a faulty GDB and made sure the test
> failed.
>
> gdb/testsuite/ChangeLog:
> 2020-02-10 Sergio Durigan Junior <sergiodj@redhat.com>
>
> PR tui/25126
> * gdb.base/cached-source-file.c: New file.
> * gdb.base/cached-source-file.exp: New file.
>
> Change-Id: Ib1b074342ebe8613c6d1dfde631691ebdf6d81c6
> ---
> gdb/testsuite/gdb.base/cached-source-file.c | 37 ++++++++
> gdb/testsuite/gdb.base/cached-source-file.exp | 94 +++++++++++++++++++
> 2 files changed, 131 insertions(+)
> create mode 100644 gdb/testsuite/gdb.base/cached-source-file.c
> create mode 100644 gdb/testsuite/gdb.base/cached-source-file.exp
>
> diff --git a/gdb/testsuite/gdb.base/cached-source-file.c b/gdb/testsuite/gdb.base/cached-source-file.c
> new file mode 100644
> index 0000000000..9f698dcffe
> --- /dev/null
> +++ b/gdb/testsuite/gdb.base/cached-source-file.c
> @@ -0,0 +1,37 @@
> +/* This testcase is part of GDB, the GNU debugger.
> +
> + Copyright 2020 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/>. */
> +
> +/* Test for PR tui/25126.
> +
> + The .exp testcase depends on the line numbers and contents from
> + this file If you change this file, make sure to double-check the
> + testcase. */
> +
> +#include <stdio.h>
> +
> +void
> +foo (void)
> +{
> + printf ("hello\n"); /* break-here */
> +}
> +
> +int
> +main ()
> +{
> + foo ();
> + return 0;
> +}
> diff --git a/gdb/testsuite/gdb.base/cached-source-file.exp b/gdb/testsuite/gdb.base/cached-source-file.exp
> new file mode 100644
> index 0000000000..f98bec09ca
> --- /dev/null
> +++ b/gdb/testsuite/gdb.base/cached-source-file.exp
> @@ -0,0 +1,94 @@
> +# Copyright (C) 2020 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/>.
> +
> +# Test for PR tui/25126.
> +# This bug is reproducible even without using the TUI.
> +
> +standard_testfile
> +
> +# Only run on native boards.
> +if { [use_gdb_stub] || [target_info gdb_protocol] == "extended-remote" } {
> + return -1
> +}
> +
> +# Because we need to modify the source file later, it's better if we
> +# just copy if to our output directory (instead of messing with the
> +# user's source directory).
> +set newsrc [standard_output_file $testfile].c
> +file copy -force -- $srcdir/$subdir/$srcfile $newsrc
> +set srcfile $newsrc
> +
> +if { [prepare_for_testing "failed to prepare" $testfile $srcfile] } {
> + return -1
> +}
> +
> +# Get the line number for the line with the "break-here" marker.
> +set bp_line [gdb_get_line_number "break-here" $srcfile]
> +
> +if { [runto "$srcfile:$bp_line"] } {
> + pass "run to $srcfile:$bp_line"
> +} else {
> + fail "run to $srcfile:$bp_line"
> +}
> +
> +# Do a "list" and check that the printed line matches the line of the
> +# original source file.
> +gdb_test_no_output "set listsize 1"
> +gdb_test "list" "$bp_line\[ \t\]+printf \\(\"hello\\\\n\"\\); /\\* break-here \\*/" \
> + "check the first version of the source file"
> +
> +# Modify the original source file, and add an extra line into it.
> +# This only works locally because of the TCL commands.
> +set bkpsrc [standard_output_file $testfile].c.bkp
> +set bkpsrcfd [open $bkpsrc w]
> +set srcfd [open $srcfile r]
> +
> +while { [gets $srcfd line] != -1 } {
> + if { [string first "break-here" $line] != -1 } {
> + # Put a "printf" line before the "break-here" line.
> + puts $bkpsrcfd " printf (\"foo\\n\");"
> + }
> + puts $bkpsrcfd $line
> +}
> +
> +close $bkpsrcfd
> +close $srcfd
> +file rename -force $bkpsrc $srcfile
> +# Give it some time to perform the renaming. For some reason, TCL
> +# needs some time after "file rename" in order to properly rename the
> +# file.
> +sleep 1
> +
> +# Recompile the modified source. We use "gdb_compile" here instead of
> +# "prepare_for_testing" because we don't want to call "clean_restart".
> +if { [gdb_compile "${srcfile}" "${binfile}" executable {debug}] != "" } {
> + return -1
> +}
> +
> +# Rerun the program. This should not only force GDB to reload the
> +# source cache, but also to break at line 6 again, which now has
> +# different contents.
> +gdb_test_multiple "run" "rerun program" {
> + -re {The program being debugged has been started already\.\r\nStart it from the beginning\? \(y or n\) $} {
> + set binregex [string_to_regexp $binfile]
> + gdb_test "y" "\\`$binregex\\' has changed; re-reading symbols\.\r\nStarting program: ${binregex}.*" \
> + "rerun program"
> + }
> +}
> +
> +# Again, perform the listing and check that the line indeed has
> +# changed for GDB.
> +gdb_test "list" "${bp_line}\[ \t\]+printf \\(\"foo\\\\n\"\\);" \
> + "verify that the source code is properly reloaded"
>