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Pedro Alves 4655f8509f Don't run personality syscall at configure time; don't check it at all
Currently, in order to tell whether support for disabling address
space randomization on Linux is available, GDB checks if the
personality syscall works, at configure time.  I.e., it does a run
test, instead of a compile/link test:

  AC_RUN_IFELSE([PERSONALITY_TEST],
		[have_personality=true],
		[have_personality=false],

This is a bit bogus, because the machine the build is done on may not
(and is when you consider distro gdbs) be the machine that eventually
runs gdb.  It would be better if this were a compile/link test
instead, and then at runtime, GDB coped with the personality syscall
failing.  Actually, GDB already copes.

One environment where this is problematic is building GDB in a Docker
container -- by default, Docker runs the container with seccomp, with
a profile that disables the personality syscall.  You can tell Docker
to use a less restricted seccomp profile, but I think we should just
fix it in GDB.

"man 2 personality" says:

       This system call first appeared in Linux 1.1.20 (and thus first
       in a stable kernel release with Linux 1.2.0); library support
       was added in glibc 2.3.

...

       ADDR_NO_RANDOMIZE (since Linux 2.6.12)
              With this flag set, disable address-space-layout randomization.

glibc 2.3 was released in 2002.
Linux 2.6.12 was released in 2005.

The original patch that added the configure checks was submitted in
2008.  The first version of the patch that was submitted to the list
called personality from common code:

 https://sourceware.org/pipermail/gdb-patches/2008-June/058204.html

and then was moved to Linux-specific code:

 https://sourceware.org/pipermail/gdb-patches/2008-June/058209.html

Since HAVE_PERSONALITY is only checked in Linux code, and
ADDR_NO_RANDOMIZE exists for over 15 years, I propose just completely
removing the configure checks.

If for some odd reason, some remotely modern system still needs a
configure check, then we can revert this commit but drop the
AC_RUN_IFELSE in favor of always doing the AC_LINK_IFELSE
cross-compile fallback.

gdb/ChangeLog:

	* linux-nat.c (linux_nat_target::supports_disable_randomization):
	Remove references to HAVE_PERSONALITY.
	* nat/linux-personality.c: Remove references to HAVE_PERSONALITY.
	(maybe_disable_address_space_randomization)
	(~maybe_disable_address_space_randomizatio): Remove references to
	HAVE_PERSONALITY.
	* config.in, configure: Regenerate.

gdbserver/ChangeLog:

	* linux-low.cc:
	(linux_process_target::supports_disable_randomization): Remove
	reference to HAVE_PERSONALITY.
	* config.in, configure: Regenerate.

gdbsupport/ChangeLog:

	* common.m4 (personality test): Remove.
2021-05-08 13:45:36 +01:00
bfd Automatic date update in version.in 2021-05-08 00:00:38 +00:00
binutils Srop readelf's unwind decoder from complaining about x86 binaries. 2021-05-07 15:24:14 +01:00
config
contrib
cpu or1k: Implement relocation R_OR1K_GOT_AHI16 for gotha() 2021-05-06 20:51:24 +09:00
elfcpp
etc
gas Add a generic .bss directive for ELF based targets. 2021-05-07 17:08:48 +01:00
gdb Don't run personality syscall at configure time; don't check it at all 2021-05-08 13:45:36 +01:00
gdbserver Don't run personality syscall at configure time; don't check it at all 2021-05-08 13:45:36 +01:00
gdbsupport Don't run personality syscall at configure time; don't check it at all 2021-05-08 13:45:36 +01:00
gnulib gnulib: import gendocs 2021-05-04 13:50:33 -04:00
gold
gprof
include Fix .dwsect generation for XCOFF. Handle .function generated with DWARF on XCOFF. 2021-05-07 15:29:49 +01:00
intl
ld x86-64/ELF: clear src_mask for all reloc types 2021-05-07 12:05:12 +02:00
libctf libctf, ld: fix test results for upstream GCC 2021-05-06 09:31:31 +01:00
libdecnumber
libiberty libiberty: add htab_eq_string 2021-05-07 11:17:11 +01:00
opcodes or1k: Implement relocation R_OR1K_GOT_AHI16 for gotha() 2021-05-06 20:51:24 +09:00
readline
sim sim: m68hc11: fix up cycle buffer printing 2021-05-07 21:55:27 -04:00
texinfo
zlib
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ar-lib
ChangeLog Replace AC_PROG_CC with AC_PROG_CC_C99 in top level configure file. 2021-05-04 13:40:34 +01:00
compile
config-ml.in
config.guess
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configure Replace AC_PROG_CC with AC_PROG_CC_C99 in top level configure file. 2021-05-04 13:40:34 +01:00
configure.ac Replace AC_PROG_CC with AC_PROG_CC_C99 in top level configure file. 2021-05-04 13:40:34 +01:00
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		   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.