forked from Imagelibrary/binutils-gdb
b93d537fba
Due to the nature of the AArch64 SVE/SME extensions in GDB, each thread can potentially have distinct target descriptions/gdbarches. When loading a gcore-generated core file, at the moment GDB gives priority to the target description dumped to NT_GDB_TDESC. Though technically correct for most targets, it doesn't work correctly for AArch64 with SVE or SME support. The correct approach for AArch64/Linux is to either have per-thread target description notes in the corefiles or to rely on the gdbarch_core_read_description hook, so it can figure out the proper target description for a given thread based on the various available register notes. The former, although more correct, doesn't address the case of existing gdb's that only output a single target description note. This patch goes for the latter, and adds a new gdbarch hook to conditionalize the use of the corefile target description note. The hook is called use_target_description_from_corefile_notes. The hook defaults to returning true, meaning targets will use the corefile target description note. AArch64 Linux overrides the hook to return false when it detects any of the SVE or SME register notes in the corefile. Otherwise it should be fine for AArch64 Linux to use the corefile target description note. When we support per-thread target description notes, then we can augment the AArch64 Linux hook to rely on those notes. Regression-tested on aarch64-linux Ubuntu 22.04/20.04. Approved-By: Simon Marchi <simon.marchi@efficios.com> Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
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.