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On GNU/Linux archs that support displaced stepping, if /proc is not mounted, GDB gets stuck not able to step past breakpoints: (gdb) c Continuing. dl_main (phdr=<optimized out>, phnum=<optimized out>, user_entry=<optimized out>, auxv=<optimized out>) at rtld.c:2163 2163 LIBC_PROBE (init_complete, 2, LM_ID_BASE, r); Cannot find AT_ENTRY auxiliary vector entry. (gdb) c Continuing. dl_main (phdr=<optimized out>, phnum=<optimized out>, user_entry=<optimized out>, auxv=<optimized out>) at rtld.c:2163 2163 LIBC_PROBE (init_complete, 2, LM_ID_BASE, r); Cannot find AT_ENTRY auxiliary vector entry. (gdb) That's because GDB can't figure out where the scratch pad is. This is a regression introduced by the earlier changes to make the Linux native target always work in non-stop mode. This commit makes GDB detect the case and fallback to stepping over breakpoints in-line. gdb/ChangeLog: 2016-03-15 Pedro Alves <palves@redhat.com> PR gdb/19676 * infrun.c (displaced_step_prepare): Also disable displaced stepping on NOT_SUPPORTED_ERROR. * linux-tdep.c (linux_displaced_step_location): If reading auxv fails, throw NOT_SUPPORTED_ERROR instead of generic error.
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.