From 088d8e322811394203220663c3b9c925980d57a2 Mon Sep 17 00:00:00 2001

From: Marek Polacek <polacek@redhat.com>

Date: Tue, 1 Feb 2022 18:27:16 -0500

Subject: [PATCH] configure: Implement --enable-host-pie

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.

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

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.

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.

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.

zlib/ChangeLog:

	* configure.ac (--enable-host-shared): Don't set PICFLAG here.

	(--enable-host-pie): New check.  Set PICFLAG after this check.

	* configure: Regenerate.

---

 c++tools/Makefile.in      | 11 ++++++---

 c++tools/configure        | 17 +++++++++++---

 c++tools/configure.ac     | 11 +++++++--

 gcc/Makefile.in           | 29 ++++++++++++++----------

 gcc/configure             | 47 +++++++++++++++++++++++++++------------

 gcc/configure.ac          | 36 +++++++++++++++++++++---------

 gcc/d/Make-lang.in        |  2 +-

 gcc/doc/install.texi      | 16 +++++++++++--

 libcody/Makefile.in       |  2 +-

 libcody/configure         | 30 ++++++++++++++++++++++++-

 libcody/configure.ac      | 26 ++++++++++++++++++++--

 libcpp/configure          | 22 +++++++++++++++++-

 libcpp/configure.ac       | 19 ++++++++++++++--

 libdecnumber/configure    | 22 +++++++++++++++++-

 libdecnumber/configure.ac | 19 ++++++++++++++--

 zlib/configure            | 30 ++++++++++++++++++++-----

 zlib/configure.ac         | 21 ++++++++++++++---

 17 files changed, 295 insertions(+), 65 deletions(-)

diff --git a/c++tools/Makefile.in b/c++tools/Makefile.in

index d6a33613732..4d5a5b0522b 100644

--- a/c++tools/Makefile.in

+++ b/c++tools/Makefile.in

@@ -28,8 +28,9 @@ AUTOCONF := @AUTOCONF@

 AUTOHEADER := @AUTOHEADER@

 CXX := @CXX@

 CXXFLAGS := @CXXFLAGS@

-PIEFLAG := @PIEFLAG@

-CXXOPTS := $(CXXFLAGS) $(PIEFLAG) -fno-exceptions -fno-rtti

+PICFLAG := @PICFLAG@

+LD_PICFLAG := @LD_PICFLAG@

+CXXOPTS := $(CXXFLAGS) $(PICFLAG) -fno-exceptions -fno-rtti

 LDFLAGS := @LDFLAGS@

 exeext := @EXEEXT@

 LIBIBERTY := ../libiberty/libiberty.a

@@ -87,11 +88,15 @@ ifeq (@CXX_AUX_TOOLS@,yes)

 all::g++-mapper-server$(exeext)

+ifneq ($(PICFLAG),)

+override LIBIBERTY := ../libiberty/pic/libiberty.a

+endif

+

 MAPPER.O := server.o resolver.o

 CODYLIB = ../libcody/libcody.a

 CXXINC += -I$(srcdir)/../libcody -I$(srcdir)/../include -I$(srcdir)/../gcc -I.

 g++-mapper-server$(exeext): $(MAPPER.O) $(CODYLIB)

-	+$(CXX) $(LDFLAGS) $(PIEFLAG) -o $@ $^ $(VERSION.O) $(LIBIBERTY) $(NETLIBS)

+	+$(CXX) $(LDFLAGS) $(PICFLAG) $(LD_PICFLAG) -o $@ $^ $(VERSION.O) $(LIBIBERTY) $(NETLIBS)

 # copy to gcc dir so tests there can run

 all::../gcc/g++-mapper-server$(exeext)

diff --git a/c++tools/configure b/c++tools/configure

index 742816e4253..88087009383 100755

--- a/c++tools/configure

+++ b/c++tools/configure

@@ -630,7 +630,8 @@ CPP

 ac_ct_CC

 CFLAGS

 CC

-PIEFLAG

+LD_PICFLAG

+PICFLAG

 MAINTAINER

 CXX_AUX_TOOLS

 AUTOHEADER

@@ -702,6 +703,7 @@ enable_option_checking

 enable_c___tools

 enable_maintainer_mode

 enable_default_pie

+enable_host_pie

 with_gcc_major_version_only

 '

       ac_precious_vars='build_alias

@@ -1333,6 +1335,7 @@ Optional Features:

                           enable maintainer mode. Add rules to rebuild

                           configurey bits

   --enable-default-pie    enable Position Independent Executable as default

+  --enable-host-pie       build host code as PIE

 Optional Packages:

   --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]

@@ -2992,12 +2995,20 @@ test "$maintainer_mode" = yes && MAINTAI

 # Check whether --enable-default-pie was given.

 # Check whether --enable-default-pie was given.

 if test "${enable_default_pie+set}" = set; then :

-  enableval=$enable_default_pie; PIEFLAG=-fPIE

+  enableval=$enable_default_pie; PICFLAG=-fPIE

 else

-  PIEFLAG=

+  PICFLAG=

 fi

+# Enable --enable-host-pie

+# Check whether --enable-host-pie was given.

+if test "${enable_host_pie+set}" = set; then :

+  enableval=$enable_host_pie; PICFLAG=-fPIE; LD_PICFLAG=-pie

+fi

+

+

+

 # Check if O_CLOEXEC is defined by fcntl

 ac_ext=c

diff --git a/c++tools/configure.ac b/c++tools/configure.ac

index 6662b5ad7c9..1e42689f2eb 100644

--- a/c++tools/configure.ac

+++ b/c++tools/configure.ac

@@ -102,8 +102,15 @@ fi

 AC_ARG_ENABLE(default-pie,

 [AS_HELP_STRING([--enable-default-pie],

 		  [enable Position Independent Executable as default])],

-[PIEFLAG=-fPIE], [PIEFLAG=])

-AC_SUBST([PIEFLAG])

+[PICFLAG=-fPIE], [PICFLAG=])

+

+# Enable --enable-host-pie

+AC_ARG_ENABLE(host-pie,

+[AS_HELP_STRING([--enable-host-pie],

+		[build host code as PIE])],

+[PICFLAG=-fPIE; LD_PICFLAG=-pie], [])

+AC_SUBST(PICFLAG)

+AC_SUBST(LD_PICFLAG)

 # Check if O_CLOEXEC is defined by fcntl

 AC_CACHE_CHECK(for O_CLOEXEC, ac_cv_o_cloexec, [

diff --git a/gcc/Makefile.in b/gcc/Makefile.in

index 31ff95500c9..151dbfa54ec 100644

--- a/gcc/Makefile.in

+++ b/gcc/Makefile.in

@@ -155,6 +155,9 @@ LDFLAGS = @LDFLAGS@

 # Should we build position-independent host code?

 PICFLAG = @PICFLAG@

+# The linker flag for the above.

+LD_PICFLAG = @LD_PICFLAG@

+

 # Flags to determine code coverage. When coverage is disabled, this will

 # contain the optimization flags, as you normally want code coverage

 # without optimization.

@@ -263,18 +266,17 @@ LINKER = $(CC)

 LINKER_FLAGS = $(CFLAGS)

 endif

+enable_host_pie = @enable_host_pie@

+

 # Enable Intel CET on Intel CET enabled host if needed.

 CET_HOST_FLAGS = @CET_HOST_FLAGS@

 COMPILER += $(CET_HOST_FLAGS)

-NO_PIE_CFLAGS = @NO_PIE_CFLAGS@

-NO_PIE_FLAG = @NO_PIE_FLAG@

-

-# We don't want to compile the compilers with -fPIE, it make PCH fail.

-COMPILER += $(NO_PIE_CFLAGS)

+# Maybe compile the compilers with -fPIE or -fPIC.

+COMPILER += $(PICFLAG)

-# Link with -no-pie since we compile the compiler with -fno-PIE.

-LINKER += $(NO_PIE_FLAG)

+# Link with -pie, or -no-pie, depending on the above.

+LINKER += $(LD_PICFLAG)

 # Like LINKER, but use a mutex for serializing front end links.

 ifeq (@DO_LINK_MUTEX@,true)

@@ -1057,18 +1059,21 @@ ALL_CPPFLAGS = $(INCLUDES) $(CPPFLAGS)

 ALL_COMPILERFLAGS = $(ALL_CXXFLAGS)

 # This is the variable to use when using $(LINKER).

-ALL_LINKERFLAGS = $(ALL_CXXFLAGS)

+ALL_LINKERFLAGS = $(ALL_CXXFLAGS) $(LD_PICFLAG)

 # Build and host support libraries.

-# Use the "pic" build of libiberty if --enable-host-shared, unless we are

-# building for mingw.

+# Use the "pic" build of libiberty if --enable-host-shared or --enable-host-pie,

+# unless we are building for mingw.

 LIBIBERTY_PICDIR=$(if $(findstring mingw,$(target)),,pic)

-ifeq ($(enable_host_shared),yes)

+ifneq ($(enable_host_shared)$(enable_host_pie),)

 LIBIBERTY = ../libiberty/$(LIBIBERTY_PICDIR)/libiberty.a

-BUILD_LIBIBERTY = $(build_libobjdir)/libiberty/$(LIBIBERTY_PICDIR)/libiberty.a

 else

 LIBIBERTY = ../libiberty/libiberty.a

+endif

+ifeq ($(enable_host_shared),yes)

+BUILD_LIBIBERTY = $(build_libobjdir)/libiberty/$(LIBIBERTY_PICDIR)/libiberty.a

+else

 BUILD_LIBIBERTY = $(build_libobjdir)/libiberty/libiberty.a

 endif

diff --git a/gcc/configure b/gcc/configure

index 258b17a226e..bd4fe1fd6ca 100755

--- a/gcc/configure

+++ b/gcc/configure

@@ -632,10 +632,10 @@ ac_includes_default="\

 ac_subst_vars='LTLIBOBJS

 LIBOBJS

 CET_HOST_FLAGS

-NO_PIE_FLAG

-NO_PIE_CFLAGS

-enable_default_pie

+LD_PICFLAG

 PICFLAG

+enable_default_pie

+enable_host_pie

 enable_host_shared

 enable_plugin

 pluginlibs

@@ -1025,6 +1025,7 @@ enable_link_serialization

 enable_version_specific_runtime_libs

 enable_plugin

 enable_host_shared

+enable_host_pie

 enable_libquadmath_support

 with_linker_hash_style

 with_diagnostics_color

@@ -1787,6 +1788,7 @@ Optional Features:

                           in a compiler-specific directory

   --enable-plugin         enable plugin support

   --enable-host-shared    build host code as shared libraries

+  --enable-host-pie       build host code as PIE

   --disable-libquadmath-support

                           disable libquadmath support for Fortran

   --enable-default-pie    enable Position Independent Executable as default

@@ -19659,7 +19661,7 @@ else

   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2

   lt_status=$lt_dlunknown

   cat > conftest.$ac_ext <<_LT_EOF

-#line 19395 "configure"

+#line 19409 "configure"

 #include "confdefs.h"

 #if HAVE_DLFCN_H

@@ -19765,7 +19767,7 @@ else

   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2

   lt_status=$lt_dlunknown

   cat > conftest.$ac_ext <<_LT_EOF

-#line 19501 "configure"

+#line 19515 "configure"

 #include "confdefs.h"

 #if HAVE_DLFCN_H

@@ -32221,13 +32223,17 @@ fi

 # Enable --enable-host-shared

 # Check whether --enable-host-shared was given.

 if test "${enable_host_shared+set}" = set; then :

-  enableval=$enable_host_shared; PICFLAG=-fPIC

-else

-  PICFLAG=

+  enableval=$enable_host_shared;

 fi

+# Enable --enable-host-pie

+# Check whether --enable-host-pie was given.

+if test "${enable_host_pie+set}" = set; then :

+  enableval=$enable_host_pie;

+fi

+

 # Check whether --enable-libquadmath-support was given.

@@ -32381,10 +32387,6 @@ rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext

 fi

 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $gcc_cv_c_no_fpie" >&5

 $as_echo "$gcc_cv_c_no_fpie" >&6; }

-if test "$gcc_cv_c_no_fpie" = "yes"; then

-  NO_PIE_CFLAGS="-fno-PIE"

-fi

-

 # Check if -no-pie works.

 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -no-pie option" >&5

@@ -32409,11 +32411,28 @@ rm -f core conftest.err conftest.$ac_objext \

 fi

 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $gcc_cv_no_pie" >&5

 $as_echo "$gcc_cv_no_pie" >&6; }

-if test "$gcc_cv_no_pie" = "yes"; then

-  NO_PIE_FLAG="-no-pie"

+

+if test x$enable_host_shared = xyes; then

+  PICFLAG=-fPIC

+elif test x$enable_host_pie = xyes; then

+  PICFLAG=-fPIE

+elif test x$gcc_cv_c_no_fpie = xyes; then

+  PICFLAG=-fno-PIE

+else

+  PICFLAG=

+fi

+

+if test x$enable_host_pie = xyes; then

+  LD_PICFLAG=-pie

+elif test x$gcc_cv_no_pie = xyes; then

+  LD_PICFLAG=-no-pie

+else

+  LD_PICFLAG=

 fi

+

+

 # Enable Intel CET on Intel CET enabled host if jit is enabled.

  # Check whether --enable-cet was given.

 if test "${enable_cet+set}" = set; then :

diff --git a/gcc/configure.ac b/gcc/configure.ac

index 06750cee977..dca995aeec7 100644

--- a/gcc/configure.ac

+++ b/gcc/configure.ac

@@ -7488,11 +7488,14 @@ fi

 # Enable --enable-host-shared

 AC_ARG_ENABLE(host-shared,

 [AS_HELP_STRING([--enable-host-shared],

-		[build host code as shared libraries])],

-[PICFLAG=-fPIC], [PICFLAG=])

+		[build host code as shared libraries])])

 AC_SUBST(enable_host_shared)

-AC_SUBST(PICFLAG)

+# Enable --enable-host-pie

+AC_ARG_ENABLE(host-pie,

+[AS_HELP_STRING([--enable-host-pie],

+		[build host code as PIE])])

+AC_SUBST(enable_host_pie)

 AC_ARG_ENABLE(libquadmath-support,

 [AS_HELP_STRING([--disable-libquadmath-support],

@@ -7614,10 +7617,6 @@ AC_CACHE_CHECK([for -fno-PIE option],

      [gcc_cv_c_no_fpie=yes],

      [gcc_cv_c_no_fpie=no])

    CXXFLAGS="$saved_CXXFLAGS"])

-if test "$gcc_cv_c_no_fpie" = "yes"; then

-  NO_PIE_CFLAGS="-fno-PIE"

-fi

-AC_SUBST([NO_PIE_CFLAGS])

 # Check if -no-pie works.

 AC_CACHE_CHECK([for -no-pie option],

@@ -7628,10 +7627,27 @@ AC_CACHE_CHECK([for -no-pie option],

      [gcc_cv_no_pie=yes],

      [gcc_cv_no_pie=no])

    LDFLAGS="$saved_LDFLAGS"])

-if test "$gcc_cv_no_pie" = "yes"; then

-  NO_PIE_FLAG="-no-pie"

+

+if test x$enable_host_shared = xyes; then

+  PICFLAG=-fPIC

+elif test x$enable_host_pie = xyes; then

+  PICFLAG=-fPIE

+elif test x$gcc_cv_c_no_fpie = xyes; then

+  PICFLAG=-fno-PIE

+else

+  PICFLAG=

 fi

-AC_SUBST([NO_PIE_FLAG])

+

+if test x$enable_host_pie = xyes; then

+  LD_PICFLAG=-pie

+elif test x$gcc_cv_no_pie = xyes; then

+  LD_PICFLAG=-no-pie

+else

+  LD_PICFLAG=

+fi

+

+AC_SUBST([PICFLAG])

+AC_SUBST([LD_PICFLAG])

 # Enable Intel CET on Intel CET enabled host if jit is enabled.

 GCC_CET_HOST_FLAGS(CET_HOST_FLAGS)

diff --git a/gcc/doc/install.texi b/gcc/doc/install.texi

index 93eae1f2582..be6985646b2 100644

--- a/gcc/doc/install.texi

+++ b/gcc/doc/install.texi

@@ -1021,14 +1021,26 @@ code.

 @item --enable-host-shared

 Specify that the @emph{host} code should be built into position-independent

-machine code (with -fPIC), allowing it to be used within shared libraries,

-but yielding a slightly slower compiler.

+machine code (with @option{-fPIC}), allowing it to be used within shared

+libraries, but yielding a slightly slower compiler.

 This option is required when building the libgccjit.so library.

 Contrast with @option{--enable-shared}, which affects @emph{target}

 libraries.

+@item --enable-host-pie

+Specify that the @emph{host} executables should be built into

+position-independent executables (with @option{-fPIE} and @option{-pie}),

+yielding a slightly slower compiler (but faster than

+@option{--enable-host-shared}).  Position-independent executables are loaded

+at random addresses each time they are executed, therefore provide additional

+protection against Return Oriented Programming (ROP) attacks.

+

+@option{--enable-host-pie}) may be used with @option{--enable-host-shared}),

+in which case @option{-fPIC} is used when compiling, and @option{-pie} when

+linking.

+

 @item @anchor{with-gnu-as}--with-gnu-as

 Specify that the compiler should assume that the

 assembler it finds is the GNU assembler.  However, this does not modify

diff --git a/libcody/Makefile.in b/libcody/Makefile.in

index 7eaf8ace8ce..0ff1625a39f 100644

--- a/libcody/Makefile.in

+++ b/libcody/Makefile.in

@@ -31,7 +31,7 @@ endif

 CXXOPTS += $(filter-out -DHAVE_CONFIG_H,@DEFS@) -include config.h

 # Linker options

-LDFLAGS := @LDFLAGS@

+LDFLAGS := @LDFLAGS@ @LD_PICFLAG@

 LIBS := @LIBS@

 # Per-source & per-directory compile flags (warning: recursive)

diff --git a/libcody/configure b/libcody/configure

index da52a5cfca5..0e536c0ccb0 100755

--- a/libcody/configure

+++ b/libcody/configure

@@ -591,7 +591,10 @@ configure_args

 AR

 RANLIB

 EXCEPTIONS

+LD_PICFLAG

 PICFLAG

+enable_host_pie

+enable_host_shared

 OBJEXT

 EXEEXT

 ac_ct_CXX

@@ -653,6 +656,7 @@ enable_maintainer_mode

 with_compiler

 enable_checking

 enable_host_shared

+enable_host_pie

 enable_exceptions

 '

       ac_precious_vars='build_alias

@@ -1286,6 +1290,7 @@ Optional Features:

                           yes,no,all,none,release. Flags are: misc,valgrind or

                           other strings

   --enable-host-shared    build host code as shared libraries

+  --enable-host-pie       build host code as PIE

   --enable-exceptions     enable exceptions & rtti

 Optional Packages:

@@ -2635,11 +2640,34 @@ fi

 # Enable --enable-host-shared.

 # Check whether --enable-host-shared was given.

 if test "${enable_host_shared+set}" = set; then :

-  enableval=$enable_host_shared; PICFLAG=-fPIC

+  enableval=$enable_host_shared;

+fi

+

+

+

+# Enable --enable-host-pie.

+# Check whether --enable-host-pie was given.

+if test "${enable_host_pie+set}" = set; then :

+  enableval=$enable_host_pie;

+fi

+

+

+

+if test x$enable_host_shared = xyes; then

+  PICFLAG=-fPIC

+elif test x$enable_host_pie = xyes; then

+  PICFLAG=-fPIE

 else

   PICFLAG=

 fi

+if test x$enable_host_pie = xyes; then

+  LD_PICFLAG=-pie

+else

+  LD_PICFLAG=

+fi

+

+

 # Check whether --enable-exceptions was given.

diff --git a/libcody/configure.ac b/libcody/configure.ac

index 960191ecb72..14e8dd4a226 100644

--- a/libcody/configure.ac

+++ b/libcody/configure.ac

@@ -63,9 +63,31 @@ fi

 # Enable --enable-host-shared.

 AC_ARG_ENABLE(host-shared,

 [AS_HELP_STRING([--enable-host-shared],

-		[build host code as shared libraries])],

-[PICFLAG=-fPIC], [PICFLAG=])

+		[build host code as shared libraries])])

+AC_SUBST(enable_host_shared)

+

+# Enable --enable-host-pie.

+AC_ARG_ENABLE(host-pie,

+[AS_HELP_STRING([--enable-host-pie],

+		[build host code as PIE])])

+AC_SUBST(enable_host_pie)

+

+if test x$enable_host_shared = xyes; then

+  PICFLAG=-fPIC

+elif test x$enable_host_pie = xyes; then

+  PICFLAG=-fPIE

+else

+  PICFLAG=

+fi

+

+if test x$enable_host_pie = xyes; then

+  LD_PICFLAG=-pie

+else

+  LD_PICFLAG=

+fi

+

 AC_SUBST(PICFLAG)

+AC_SUBST(LD_PICFLAG)

 NMS_ENABLE_EXCEPTIONS

diff --git a/libcpp/configure b/libcpp/configure

index 75145390215..85168273cd1 100755

--- a/libcpp/configure

+++ b/libcpp/configure

@@ -625,6 +625,8 @@ ac_includes_default="\

 ac_subst_vars='LTLIBOBJS

 CET_HOST_FLAGS

 PICFLAG

+enable_host_pie

+enable_host_shared

 MAINT

 USED_CATALOGS

 PACKAGE

@@ -738,6 +740,7 @@ enable_maintainer_mode

 enable_checking

 enable_canonical_system_headers

 enable_host_shared

+enable_host_pie

 enable_cet

 enable_valgrind_annotations

 '

@@ -1379,6 +1382,7 @@ Optional Features:

   --enable-canonical-system-headers

                           enable or disable system headers canonicalization

   --enable-host-shared    build host code as shared libraries

+  --enable-host-pie       build host code as PIE

   --enable-cet            enable Intel CET in host libraries [default=auto]

   --enable-valgrind-annotations

                           enable valgrind runtime interaction

@@ -7605,7 +7609,23 @@ esac

 # Enable --enable-host-shared.

 # Check whether --enable-host-shared was given.

 if test "${enable_host_shared+set}" = set; then :

-  enableval=$enable_host_shared; PICFLAG=-fPIC

+  enableval=$enable_host_shared;

+fi

+

+

+

+# Enable --enable-host-pie.

+# Check whether --enable-host-pie was given.

+if test "${enable_host_pie+set}" = set; then :

+  enableval=$enable_host_pie;

+fi

+

+

+

+if test x$enable_host_shared = xyes; then

+  PICFLAG=-fPIC

+elif test x$enable_host_pie = xyes; then

+  PICFLAG=-fPIE

 else

   PICFLAG=

 fi

diff --git a/libcpp/configure.ac b/libcpp/configure.ac

index 9b6042518e5..d25bf5f414f 100644

--- a/libcpp/configure.ac

+++ b/libcpp/configure.ac

@@ -211,8 +211,23 @@ esac

 # Enable --enable-host-shared.

 AC_ARG_ENABLE(host-shared,

 [AS_HELP_STRING([--enable-host-shared],

-		[build host code as shared libraries])],

-[PICFLAG=-fPIC], [PICFLAG=])

+		[build host code as shared libraries])])

+AC_SUBST(enable_host_shared)

+

+# Enable --enable-host-pie.

+AC_ARG_ENABLE(host-pie,

+[AS_HELP_STRING([--enable-host-pie],

+		[build host code as PIE])])

+AC_SUBST(enable_host_pie)

+

+if test x$enable_host_shared = xyes; then

+  PICFLAG=-fPIC

+elif test x$enable_host_pie = xyes; then

+  PICFLAG=-fPIE

+else

+  PICFLAG=

+fi

+

 AC_SUBST(PICFLAG)

 # Enable Intel CET on Intel CET enabled host if jit is enabled.

diff --git a/libdecnumber/configure b/libdecnumber/configure

index da5302f9315..d805fdeab5a 100755

--- a/libdecnumber/configure

+++ b/libdecnumber/configure

@@ -626,6 +626,8 @@ ac_subst_vars='LTLIBOBJS

 LIBOBJS

 CET_HOST_FLAGS

 PICFLAG

+enable_host_pie

+enable_host_shared

 ADDITIONAL_OBJS

 enable_decimal_float

 target_os

@@ -706,6 +708,7 @@ enable_werror_always

 enable_maintainer_mode

 enable_decimal_float

 enable_host_shared

+enable_host_pie

 enable_cet

 '

       ac_precious_vars='build_alias

@@ -1338,6 +1341,7 @@ Optional Features:

 			or 'dpd' choses which decimal floating point format

 			to use

   --enable-host-shared    build host code as shared libraries

+  --enable-host-pie       build host code as PIE

   --enable-cet            enable Intel CET in host libraries [default=auto]

 Some influential environment variables:

@@ -5185,7 +5189,23 @@ $as_echo "#define AC_APPLE_UNIVERSAL_BUILD 1" >>confdefs.h

 # Enable --enable-host-shared.

 # Check whether --enable-host-shared was given.

 if test "${enable_host_shared+set}" = set; then :

-  enableval=$enable_host_shared; PICFLAG=-fPIC

+  enableval=$enable_host_shared;

+fi

+

+

+

+# Enable --enable-host-pie.

+# Check whether --enable-host-pie was given.

+if test "${enable_host_pie+set}" = set; then :

+  enableval=$enable_host_pie;

+fi

+

+