From d5a6313e1c4c748a7e744514dbabfa001636f09a Mon Sep 17 00:00:00 2001 From: Simon Marchi Date: Thu, 27 May 2021 13:59:01 -0400 Subject: [PATCH] gdb: add option to reverse order of _initialize function calls An earlier patch in this series fixed a dependency problem between two _initialize functions. That problem was uncovered by reversing the order of the initialize function calls. In short, symtab.c tried to add the alias "maintenance flush-symbol-cache" for the command "maintenance flush symbol-cache". Because the "maintenance flush" prefix command was not yet created (it happens in maint.c, initialized later in this reversed order), the add_alias_cmd function returned NULL. That result was passed to deprecate_cmd, which didn't expected that value, and that caused a segfault. This was fixed by changing alias creation functions to take the target command as a cmd_list_element, instead of by name. This patch adds a runtime option to reverse the order of the initialize calls at will. I chose to use an environment variable for this, over a parameter (even a "maintenance" one), because: - The init functions are called before the early init commands are executed, so we could use -iex to turn this mode on early enough. This is obvious when you remember that commands / parameters are created by initialize funcitions :). - This is not something anybody would want to tweak after startup anyway. gdb/ChangeLog: * make-init-c: Add option to reverse function calls. gdb/testsuite/ChangeLog: * gdb.base/reverse-init-functions.exp: New. Change-Id: I543e609cf526e7cb145a006a794d0e6851b63f45 --- gdb/ChangeLog | 4 +++ gdb/make-init-c | 15 +++++++++- gdb/testsuite/ChangeLog | 4 +++ .../gdb.base/reverse-init-functions.exp | 29 +++++++++++++++++++ 4 files changed, 51 insertions(+), 1 deletion(-) create mode 100644 gdb/testsuite/gdb.base/reverse-init-functions.exp diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 1db1264c302..9d06a771ae5 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,7 @@ +2021-05-27 Simon Marchi + + * make-init-c: Add option to reverse function calls. + 2021-05-27 Simon Marchi * Makefile.in (INIT_FILES_FILTER_OUT): New. diff --git a/gdb/make-init-c b/gdb/make-init-c index 1588760112e..e3c5985f133 100755 --- a/gdb/make-init-c +++ b/gdb/make-init-c @@ -42,6 +42,7 @@ set -e echo "/* Do not modify this file. */" echo "/* It is created automatically by the Makefile. */" echo "#include \"defs.h\" /* For initialize_file_ftype. */" +echo "#include " echo "" sed -n -e 's/^\(_initialize_[a-zA-Z0-9_]*\) ()$/\1/p' "$@" | while read -r name; do echo "extern initialize_file_ftype $name;" @@ -51,7 +52,19 @@ echo "void initialize_all_files ();" echo "void" echo "initialize_all_files ()" echo "{" +echo " std::vector functions =" +echo " {" sed -n -e 's/^\(_initialize_[a-zA-Z0-9_]*\) ()$/\1/p' "$@" | while read -r name; do - echo " $name ();" + echo " $name," done +echo " };" +echo "" +echo " /* If GDB_REVERSE_INIT_FUNCTIONS is set (any value), reverse the" +echo " order in which initialization functions are called. This is" +echo " used by the testsuite. */" +echo " if (getenv (\"GDB_REVERSE_INIT_FUNCTIONS\") != nullptr)" +echo " std::reverse (functions.begin (), functions.end ());" +echo "" +echo " for (initialize_file_ftype *function : functions)" +echo " function ();" echo "}" diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index 22a99c0cc5e..e2a95d48c33 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2021-05-27 Simon Marchi + + * gdb.base/reverse-init-functions.exp: New. + 2021-05-27 Tom de Vries PR symtab/27919 diff --git a/gdb/testsuite/gdb.base/reverse-init-functions.exp b/gdb/testsuite/gdb.base/reverse-init-functions.exp new file mode 100644 index 00000000000..76fa793acb3 --- /dev/null +++ b/gdb/testsuite/gdb.base/reverse-init-functions.exp @@ -0,0 +1,29 @@ +# Copyright 2020-2021 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 . + +# Test reversing the order of initialize functions calls, during GDB startup. +# +# The intent is to catch possible unintended dependencies between two +# initialize functions, where one depends on the other running before it. + +standard_testfile + +save_vars { env(GDB_REVERSE_INIT_FUNCTIONS) } { + setenv GDB_REVERSE_INIT_FUNCTIONS 1 + clean_restart +} + +# Verify that GDB has started and is ready to accept commands. +gdb_test "print 12321" " = 12321" -- 2.30.2