gcc/libiberty
Marek Polacek b6cb10af12 configure: Implement --enable-host-pie
[ This is my third attempt to add this configure option.  The first
version was approved but it came too late in the development cycle.
The second version was also approved, but I had to revert it:
<https://gcc.gnu.org/pipermail/gcc-patches/2022-November/607082.html>.
I've fixed the problem (by moving $(PICFLAG) from INTERNAL_CFLAGS to
ALL_COMPILERFLAGS).  Another change is that since r13-4536 I no longer
need to touch Makefile.def, so this patch is simplified. ]

This patch implements the --enable-host-pie configure option which
makes the compiler executables PIE.  This can be used to enhance
protection against ROP attacks, and can be viewed as part of a wider
trend to harden binaries.

It is similar to the option --enable-host-shared, except that --e-h-s
won't add -shared to the linker flags whereas --e-h-p will add -pie.
It is different from --enable-default-pie because that option just
adds an implicit -fPIE/-pie when the compiler is invoked, but the
compiler itself isn't PIE.

Since r12-5768-gfe7c3ecf, PCH works well with PIE, so there are no PCH
regressions.

When building the compiler, the build process may use various in-tree
libraries; these need to be built with -fPIE so that it's possible to
use them when building a PIE.  For instance, when --with-included-gettext
is in effect, intl object files must be compiled with -fPIE.  Similarly,
when building in-tree gmp, isl, mpfr and mpc, they must be compiled with
-fPIE.

With this patch and --enable-host-pie used to configure gcc:

$ file gcc/cc1{,plus,obj,gm2} gcc/f951 gcc/lto1 gcc/cpp gcc/go1 gcc/rust1 gcc/gnat1
gcc/cc1:     ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=98e22cde129d304aa6f33e61b1c39e144aeb135e, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/cc1plus: ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=859d1ea37e43dfe50c18fd4e3dd9a34bb1db8f77, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/cc1obj:  ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=1964f8ecee6163182bc26134e2ac1f324816e434, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/cc1gm2:  ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=a396672c7ff913d21855829202e7b02ecf42ff4c, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/f951:    ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=59c523db893186547ac75c7a71f48be0a461c06b, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/lto1:    ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=084a7b77df7be2d63c2d4c655b5bbc3fcdb6038d, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/cpp:     ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=3503bf8390d219a10d6653b8560aa21158132168, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/go1:     ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=988cc673af4fba5dcb482f4b34957b99050a68c5, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/rust1:   ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=b6a5d3d514446c4dcdee0707f086ab9b274a8a3c, for GNU/Linux 3.2.0, with debug_info, not stripped
gcc/gnat1:   ELF 64-bit LSB pie executable, x86-64, version 1 (GNU/Linux), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=bb11ccdc2c366fe3fe0980476bcd8ca19b67f9dc, for GNU/Linux 3.2.0, with debug_info, not stripped

I plan to add an option to link with -Wl,-z,now.

Bootstrapped on x86_64-pc-linux-gnu with --with-included-gettext
--enable-host-pie as well as without --enable-host-pie.  Also tested
on a Debian system where the system gcc was configured with
--enable-default-pie.

Co-Authored by: Iain Sandoe  <iain@sandoe.co.uk>

ChangeLog:

	* configure.ac (--enable-host-pie): New check.  Set PICFLAG after this
	check.
	* configure: Regenerate.

c++tools/ChangeLog:

	* Makefile.in: Rename PIEFLAG to PICFLAG.  Set LD_PICFLAG.  Use it.
	Use pic/libiberty.a if PICFLAG is set.
	* configure.ac (--enable-default-pie): Set PICFLAG instead of PIEFLAG.
	(--enable-host-pie): New check.
	* configure: Regenerate.

fixincludes/ChangeLog:

	* Makefile.in: Set and use PICFLAG and LD_PICFLAG.  Use the "pic"
	build of libiberty if PICFLAG is set.
	* configure.ac:
	* configure: Regenerate.

gcc/ChangeLog:

	* Makefile.in: Set LD_PICFLAG.  Use it.  Set enable_host_pie.
	Remove NO_PIE_CFLAGS and NO_PIE_FLAG.  Pass LD_PICFLAG to
	ALL_LINKERFLAGS.  Use the "pic" build of libiberty if --enable-host-pie.
	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG and LD_PICFLAG after this
	check.
	* configure: Regenerate.
	* doc/install.texi: Document --enable-host-pie.

gcc/ada/ChangeLog:

	* gcc-interface/Make-lang.in (ALL_ADAFLAGS): Remove NO_PIE_CFLAGS.  Add
	PICFLAG.  Use PICFLAG when building ada/b_gnat1.o and ada/b_gnatb.o.
	* gcc-interface/Makefile.in: Use pic/libiberty.a if PICFLAG is set.
	Remove NO_PIE_FLAG.

gcc/m2/ChangeLog:

	* Make-lang.in: New var, GM2_PICFLAGS.  Use it.

gcc/d/ChangeLog:

	* Make-lang.in: Remove NO_PIE_CFLAGS.

intl/ChangeLog:

	* Makefile.in: Use @PICFLAG@ in COMPILE as well.
	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG after this check.
	* configure: Regenerate.

libcody/ChangeLog:

	* Makefile.in: Pass LD_PICFLAG to LDFLAGS.
	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG and LD_PICFLAG after this
	check.
	* configure: Regenerate.

libcpp/ChangeLog:

	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG after this check.
	* configure: Regenerate.

libdecnumber/ChangeLog:

	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG after this check.
	* configure: Regenerate.

libiberty/ChangeLog:

	* configure.ac: Also set shared when enable_host_pie.
	* configure: Regenerate.

zlib/ChangeLog:

	* configure.ac (--enable-host-shared): Don't set PICFLAG here.
	(--enable-host-pie): New check.  Set PICFLAG after this check.
	* configure: Regenerate.
2023-06-15 16:51:27 -04:00
..
config
testsuite c++: Fix templated convertion operator demangling 2023-06-13 17:07:01 -04:00
_doprnt.c Update copyright years. 2023-01-16 11:52:17 +01:00
.gitignore
acinclude.m4 Update copyright years. 2023-01-16 11:52:17 +01:00
aclocal.m4
alloca.c
argv.c libiberty: writeargv: Simplify function error mode. 2023-06-06 20:50:07 -06:00
asprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
at-file.texi Revert "sphinx: remove texinfo files" 2022-11-14 09:35:06 +01:00
atexit.c
basename.c
bcmp.c
bcopy.c
bsearch_r.c
bsearch.c
bzero.c
calloc.c
ChangeLog Daily bump. 2023-06-14 00:17:28 +00:00
ChangeLog.jit
choose-temp.c Update copyright years. 2023-01-16 11:52:17 +01:00
clock.c Update copyright years. 2023-01-16 11:52:17 +01:00
concat.c Update copyright years. 2023-01-16 11:52:17 +01:00
config.h-vms
config.in
configure configure: Implement --enable-host-pie 2023-06-15 16:51:27 -04:00
configure.ac configure: Implement --enable-host-pie 2023-06-15 16:51:27 -04:00
configure.com
copying-lib.texi Update copyright years. 2023-01-16 11:52:17 +01:00
COPYING.LIB
copysign.c
cp-demangle.c c++: Fix templated convertion operator demangling 2023-06-13 17:07:01 -04:00
cp-demangle.h Update copyright years. 2023-01-16 11:52:17 +01:00
cp-demint.c Update copyright years. 2023-01-16 11:52:17 +01:00
cplus-dem.c Update copyright years. 2023-01-16 11:52:17 +01:00
crc32.c Update copyright years. 2023-01-16 11:52:17 +01:00
d-demangle.c Update copyright years. 2023-01-16 11:52:17 +01:00
dwarfnames.c Update copyright years. 2023-01-16 11:52:17 +01:00
dyn-string.c Update copyright years. 2023-01-16 11:52:17 +01:00
fdmatch.c Update copyright years. 2023-01-16 11:52:17 +01:00
ffs.c
fibheap.c Update copyright years. 2023-01-16 11:52:17 +01:00
filedescriptor.c Update copyright years. 2023-01-16 11:52:17 +01:00
filename_cmp.c Update copyright years. 2023-01-16 11:52:17 +01:00
floatformat.c Update copyright years. 2023-01-16 11:52:17 +01:00
fnmatch.c Update copyright years. 2023-01-16 11:52:17 +01:00
fnmatch.txh
fopen_unlocked.c Update copyright years. 2023-01-16 11:52:17 +01:00
functions.texi Revert "sphinx: remove texinfo files" 2022-11-14 09:35:06 +01:00
gather-docs Update copyright years. 2023-01-16 11:52:17 +01:00
getcwd.c
getopt1.c Update copyright years. 2023-01-16 11:52:17 +01:00
getopt.c Update copyright years. 2023-01-16 11:52:17 +01:00
getpagesize.c
getpwd.c
getruntime.c Update copyright years. 2023-01-16 11:52:17 +01:00
gettimeofday.c
hashtab.c Update copyright years. 2023-01-16 11:52:17 +01:00
hex.c Update copyright years. 2023-01-16 11:52:17 +01:00
index.c
insque.c
lbasename.c Update copyright years. 2023-01-16 11:52:17 +01:00
libiberty.texi Update copyright years. 2023-01-16 11:52:17 +01:00
lrealpath.c libiberty: fix lrealpath on Windows NTFS symlinks 2023-02-11 06:29:43 +00:00
maint-tool Update copyright years. 2023-01-16 11:52:17 +01:00
make-relative-prefix.c Update copyright years. 2023-01-16 11:52:17 +01:00
make-temp-file.c Update copyright years. 2023-01-16 11:52:17 +01:00
Makefile.in Update copyright years. 2023-01-16 11:52:17 +01:00
makefile.vms
md5.c Update copyright years. 2023-01-16 11:52:17 +01:00
memchr.c
memcmp.c
memcpy.c
memmem.c Update copyright years. 2023-01-16 11:52:17 +01:00
memmove.c
mempcpy.c Update copyright years. 2023-01-16 11:52:17 +01:00
memset.c
mkstemps.c Update copyright years. 2023-01-16 11:52:17 +01:00
msdos.c
objalloc.c Update copyright years. 2023-01-16 11:52:17 +01:00
obstack.c Update copyright years. 2023-01-16 11:52:17 +01:00
obstacks.texi libiberty: Remove a reference to the Glibc manual 2023-03-30 23:41:24 +02:00
partition.c Update copyright years. 2023-01-16 11:52:17 +01:00
pex-common.c Update copyright years. 2023-01-16 11:52:17 +01:00
pex-common.h Update copyright years. 2023-01-16 11:52:17 +01:00
pex-djgpp.c Update copyright years. 2023-01-16 11:52:17 +01:00
pex-msdos.c Update copyright years. 2023-01-16 11:52:17 +01:00
pex-one.c Update copyright years. 2023-01-16 11:52:17 +01:00
pex-unix.c Update copyright years. 2023-01-16 11:52:17 +01:00
pex-win32.c libiberty: pex-win32.c: Fix some typos. 2023-06-05 12:13:28 +00:00
pexecute.c Update copyright years. 2023-01-16 11:52:17 +01:00
pexecute.txh
physmem.c Update copyright years. 2023-01-16 11:52:17 +01:00
putenv.c Update copyright years. 2023-01-16 11:52:17 +01:00
random.c
README libiberty: Refer to Bugzilla in README 2022-09-22 15:19:14 +01:00
regex.c Update copyright years. 2023-01-16 11:52:17 +01:00
rename.c
rindex.c
rust-demangle.c Update copyright years. 2023-01-16 11:52:17 +01:00
safe-ctype.c Update copyright years. 2023-01-16 11:52:17 +01:00
setenv.c Update copyright years. 2023-01-16 11:52:17 +01:00
setproctitle.c Update copyright years. 2023-01-16 11:52:17 +01:00
sha1.c Update copyright years. 2023-01-16 11:52:17 +01:00
sigsetmask.c
simple-object-coff.c Update copyright years. 2023-01-16 11:52:17 +01:00
simple-object-common.h Update copyright years. 2023-01-16 11:52:17 +01:00
simple-object-elf.c Update copyright years. 2023-01-16 11:52:17 +01:00
simple-object-mach-o.c Update copyright years. 2023-01-16 11:52:17 +01:00
simple-object-xcoff.c Update copyright years. 2023-01-16 11:52:17 +01:00
simple-object.c Update copyright years. 2023-01-16 11:52:17 +01:00
simple-object.txh
snprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
sort.c Update copyright years. 2023-01-16 11:52:17 +01:00
spaces.c Update copyright years. 2023-01-16 11:52:17 +01:00
splay-tree.c Update copyright years. 2023-01-16 11:52:17 +01:00
stack-limit.c Update copyright years. 2023-01-16 11:52:17 +01:00
stpcpy.c Update copyright years. 2023-01-16 11:52:17 +01:00
stpncpy.c Update copyright years. 2023-01-16 11:52:17 +01:00
strcasecmp.c
strchr.c
strdup.c
strerror.c
strncasecmp.c
strncmp.c
strndup.c Update copyright years. 2023-01-16 11:52:17 +01:00
strnlen.c
strrchr.c
strsignal.c
strstr.c libiberty: Make strstr.c in libiberty ANSI compliant 2023-04-02 20:05:31 +02:00
strtod.c Update copyright years. 2023-01-16 11:52:17 +01:00
strtol.c
strtoll.c
strtoul.c
strtoull.c
strverscmp.c Update copyright years. 2023-01-16 11:52:17 +01:00
timeval-utils.c Update copyright years. 2023-01-16 11:52:17 +01:00
tmpnam.c
unlink-if-ordinary.c Update copyright years. 2023-01-16 11:52:17 +01:00
vasprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
vfork.c
vfprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
vprintf-support.c Update copyright years. 2023-01-16 11:52:17 +01:00
vprintf-support.h Update copyright years. 2023-01-16 11:52:17 +01:00
vprintf.c
vsnprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
vsprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
waitpid.c
xasprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00
xatexit.c
xexit.c Update copyright years. 2023-01-16 11:52:17 +01:00
xmalloc.c Update copyright years. 2023-01-16 11:52:17 +01:00
xmemdup.c
xstrdup.c
xstrerror.c
xstrndup.c Update copyright years. 2023-01-16 11:52:17 +01:00
xvasprintf.c Update copyright years. 2023-01-16 11:52:17 +01:00

This directory contains the -liberty library of free software.
It is a collection of subroutines used by various GNU programs.
Current members include:

	getopt -- get options from command line
	obstack -- stacks of arbitrarily-sized objects
	strerror -- error message strings corresponding to errno
	strtol -- string-to-long conversion
	strtoul -- string-to-unsigned-long conversion

We expect many of the GNU subroutines that are floating around to
eventually arrive here.

The library must be configured from the top source directory.  Don't
try to run configure in this directory.  Follow the configuration
instructions in ../README.

Please report bugs to https://gcc.gnu.org/bugzilla/ and send fixes to
"gcc-patches@gcc.gnu.org".  Thank you.

ADDING A NEW FILE
=================

There are two sets of files:  Those that are "required" will be
included in the library for all configurations, while those
that are "optional" will be included in the library only if "needed."

To add a new required file, edit Makefile.in to add the source file
name to CFILES and the object file to REQUIRED_OFILES.

To add a new optional file, it must provide a single function, and the
name of the function must be the same as the name of the file.

    * Add the source file name to CFILES in Makefile.in and the object
      file to CONFIGURED_OFILES.

    * Add the function to name to the funcs shell variable in
      configure.ac.

    * Add the function to the AC_CHECK_FUNCS lists just after the
      setting of the funcs shell variable.  These AC_CHECK_FUNCS calls
      are never executed; they are there to make autoheader work
      better.

    * Consider the special cases of building libiberty; as of this
      writing, the special cases are newlib and VxWorks.  If a
      particular special case provides the function, you do not need
      to do anything.  If it does not provide the function, add the
      object file to LIBOBJS, and add the function name to the case
      controlling whether to define HAVE_func.

Finally, in the build directory of libiberty, configure with
"--enable-maintainer-mode", run "make maint-deps" to update
Makefile.in, and run 'make stamp-functions' to regenerate
functions.texi.

The optional file you've added (e.g. getcwd.c) should compile and work
on all hosts where it is needed.  It does not have to work or even
compile on hosts where it is not needed.

ADDING A NEW CONFIGURATION
==========================

On most hosts you should be able to use the scheme for automatically
figuring out which files are needed.  In that case, you probably
don't need a special Makefile stub for that configuration.

If the fully automatic scheme doesn't work, you may be able to get
by with defining EXTRA_OFILES in your Makefile stub.  This is
a list of object file names that should be treated as required
for this configuration - they will be included in libiberty.a,
regardless of whatever might be in the C library.