Binutils with MCST patches
72bc1d2466
The test py-inferior.exp fails when using a debug build of Python 3.6. I don't see it failing with my system's default Python, but it might be related to the different memory allocation scheme used when doing a build with pydebug. The issue is that we are missing a Py_INCREF in inferior_to_inferior_object. The PyObject_New function initializes the object with a refcount of 1. If we assume that this refcount corresponds to the reference we are returning, then we are missing an incref for the reference in the inferior data. The counterpart for the incref that corresponds to the reference in the inferior data is in py_free_inferior, in the form the gdbpy_ref instance. Here's how I can get it to crash (with some debug output): $ ./gdb -nx -ex "set debug python 1" (gdb) add-inferior Added inferior 2 (gdb) python infs = gdb.inferiors() Creating Python Inferior object inf = 1 Creating Python Inferior object inf = 2 (gdb) remove-inferiors 2 py_free_inferior inf = 2 infpy_dealloc inf = <unknown> (gdb) python infs = None Fatal Python error: Objects/tupleobject.c:243 object at 0x7f9cf1a568d8 has negative ref count -1 Current thread 0x00007f9cf1b68780 (most recent call first): File "<string>", line 1 in <module> [1] 408 abort (core dumped) ./gdb -nx -ex "set debug python 1" After having created the inferiors object, their refcount is 1 (which comes from PyObject_New), but it should be two. The gdb inferior object has a reference and the "infs" list has a reference. When invoking remove-inferiors, py_free_inferior gets called. It does the decref that corresponds to the reference that the gdb inferior object kept. At this moment, the refcount drops to 0 and the object gets deallocated, even though the "infs" list still has a reference. When we set "infs" to None, Python tries to decref the already zero refcount and the assert triggers. With this patch, it looks better: (gdb) add-inferior Added inferior 2 (gdb) python infs = gdb.inferiors() Creating Python Inferior object inf = 1 Creating Python Inferior object inf = 2 (gdb) remove-inferiors 2 py_free_inferior inf = 2 (gdb) python infs = None infpy_dealloc inf = <unknown> gdb/ChangeLog: * python/py-inferior.c (inferior_to_inferior_object): Increment reference count when creating the object. |
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bfd | ||
binutils | ||
config | ||
cpu | ||
elfcpp | ||
etc | ||
gas | ||
gdb | ||
gold | ||
gprof | ||
include | ||
intl | ||
ld | ||
libdecnumber | ||
libiberty | ||
opcodes | ||
readline | ||
sim | ||
texinfo | ||
zlib | ||
.cvsignore | ||
.gitattributes | ||
.gitignore | ||
ChangeLog | ||
compile | ||
config-ml.in | ||
config.guess | ||
config.rpath | ||
config.sub | ||
configure | ||
configure.ac | ||
COPYING | ||
COPYING3 | ||
COPYING3.LIB | ||
COPYING.LIB | ||
COPYING.LIBGLOSS | ||
COPYING.NEWLIB | ||
depcomp | ||
djunpack.bat | ||
install-sh | ||
libtool.m4 | ||
lt~obsolete.m4 | ||
ltgcc.m4 | ||
ltmain.sh | ||
ltoptions.m4 | ||
ltsugar.m4 | ||
ltversion.m4 | ||
MAINTAINERS | ||
Makefile.def | ||
Makefile.in | ||
Makefile.tpl | ||
makefile.vms | ||
missing | ||
mkdep | ||
mkinstalldirs | ||
move-if-change | ||
README | ||
README-maintainer-mode | ||
setup.com | ||
src-release.sh | ||
symlink-tree | ||
ylwrap |
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.