From db1f6cd692cac4818e16f9e3b43ee7802b079d1c Mon Sep 17 00:00:00 2001 From: Lancelot SIX Date: Wed, 24 Mar 2021 23:55:25 +0000 Subject: [PATCH] [PR gdb/27614] gdb-add-index fails on symlinks. PR 27614 shows that gdb-add-index fails to generate the index when its argument is a symlink. The following one liner illustrates the reported problem: $ echo 'int main(){}'|gcc -g -x c -;ln -s a.out symlink;gdb-add-index symlink gdb-add-index: No index was created for symlink gdb-add-index: [Was there no debuginfo? Was there already an index?] $ ls -l -rwxr-xr-x 1 25712 Mar 19 23:05 a.out* -rw------- 1 8277 Mar 19 23:05 a.out.gdb-index lrwxrwxrwx 1 5 Mar 19 23:05 symlink -> a.out* GDB generates the .gdb-index file with a name that matches the name of the actual program (a.out.gdb-index here), not the symlink that references it. The remaining of the script is looking for a file named after the provided argument (would be 'symlink.gdb-index' in our example). gdb/ChangeLog: PR gdb/27614 * contrib/gdb-add-index.sh: Fix when called with a symlink as an argument. gdb/testsuite/ChangeLog: PR gdb/27614 * gdb.dwarf2/gdb-add-index-symlink.exp: New test. --- gdb/ChangeLog | 6 +++ gdb/contrib/gdb-add-index.sh | 28 +++++++++++ gdb/testsuite/ChangeLog | 5 ++ .../gdb.dwarf2/gdb-add-index-symlink.exp | 47 +++++++++++++++++++ 4 files changed, 86 insertions(+) create mode 100644 gdb/testsuite/gdb.dwarf2/gdb-add-index-symlink.exp diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 52d5faac8a9..624d5793a15 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,9 @@ +2021-05-10 Lancelot Six + + PR gdb/27614 + * contrib/gdb-add-index.sh: Fix when called with a symlink as an + argument. + 2021-05-10 Simon Marchi * nat/linux-waitpid.c (status_to_str): Show signal name. diff --git a/gdb/contrib/gdb-add-index.sh b/gdb/contrib/gdb-add-index.sh index 2ac3fddbf26..734110caa3b 100755 --- a/gdb/contrib/gdb-add-index.sh +++ b/gdb/contrib/gdb-add-index.sh @@ -37,6 +37,34 @@ fi file="$1" +if test -L "$file"; then + if ! command -v readlink >/dev/null 2>&1; then + echo "$myname: 'readlink' missing. Failed to follow symlink $1." 1>&2 + exit 1 + fi + + # Count number of links followed in order to detect loops. + count=0 + while test -L "$file"; do + target=$(readlink "$file") + + case "$target" in + /*) + file="$target" + ;; + *) + file="$(dirname "$file")/$target" + ;; + esac + + count="$((count + 1))" + if test "$count" -gt 10; then + echo "$myname: Detected loop while following link $file" + exit 1 + fi + done +fi + if test ! -r "$file"; then echo "$myname: unable to access: $file" 1>&2 exit 1 diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index b3a41bd5481..c188719cd57 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2021-05-10 Lancelot Six + + PR gdb/27614 + * gdb.dwarf2/gdb-add-index-symlink.exp: New test. + 2021-05-10 Andrew Burgess * gdb.guile/guile.exp: Don't use the source directory as a diff --git a/gdb/testsuite/gdb.dwarf2/gdb-add-index-symlink.exp b/gdb/testsuite/gdb.dwarf2/gdb-add-index-symlink.exp new file mode 100644 index 00000000000..eaeddec0250 --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/gdb-add-index-symlink.exp @@ -0,0 +1,47 @@ +# Copyright 2021 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +load_lib dwarf.exp + +# This test can only be run on targets which support DWARF-2. +if {![dwarf2_support]} { + return 0 +} + +standard_testfile main.c + +if { [prepare_for_testing "failed to prepare" "${testfile}" \ + [list ${srcfile}]] } { + return -1 +} + +set symlink [file dirname $binfile]/symlink + +if { ![file exists $symlink] } { + file link -symbolic $symlink $binfile +} + +if { [ensure_gdb_index $symlink] == -1 } { + fail "Unable to call gdb-add-index with a symlink to a symfile" + return -1 +} + +# Ok, we have a copy of $binfile with an index. +# Restart gdb and verify the index was used. + +clean_restart $symlink +gdb_test "mt print objfiles ${testfile}" \ + "(gdb_index|debug_names).*" \ + "index used" -- 2.30.2