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PING: [PATCH] Add --enable-static-pie to build static PIE
- From: "H.J. Lu" <hjl dot tools at gmail dot com>
- To: GNU C Library <libc-alpha at sourceware dot org>
- Date: Mon, 11 Sep 2017 09:47:38 -0700
- Subject: PING: [PATCH] Add --enable-static-pie to build static PIE
- Authentication-results: sourceware.org; auth=none
On Fri, Sep 1, 2017 at 10:49 AM, H.J. Lu <hongjiu.lu@intel.com> wrote:
> --enable-static-pie configures glibc to compile libc.a as PIE and
> creates static executables as PIE. A static position independent
> executable (static PIE) is similar to static executable, but can be
> loaded at any address without help from a dynamic linker. All linker
> input files must be compiled with -fpie or -fPIE. "-z text" is also
> passed to linker to prevent dynamic relocations in read-only segments.
> It passes -static-pie to the GCC driver with the patch:
>
> https://gcc.gnu.org/ml/gcc-patches/2017-08/msg01455.html
>
> This patch requires:
>
> 1. Linker supports --no-dynamic-linker to remove PT_INTERP segment from
> static PIE.
> 2. Linker can create working static PIE. The x86-64 linker needs the
> fix for
>
> https://sourceware.org/bugzilla/show_bug.cgi?id=21782
>
> Binutils 2.29 or above are OK.
>
> Tested on i686 and x86-64.
>
> OK for master?
>
> H.J.
> ---
> * Makeconfig (pic-default): Updated for --enable-static-pie.
> (pie-default): New for --enable-static-pie.
> (default-pie-ldflag): Likewise.
> (+link-static-before-libc): Add $(default-pie-ldflag).
> (+prectorT): Updated for --enable-static-pie.
> (+postctorT): Likewise.
> (CFLAGS-.o): Add $(pie-default).
> (CFLAGS-.op): Likewise.
> * config.h.in (ENABLE_STATIC_PIE): New.
> * configure.ac (--enable-static-pie): New configure option.
> (have-no-dynamic-linker): New LIBC_CONFIG_VAR.
> (have-static-pie): Likewise.
> Enable static PIE if linker supports --no-dynamic-linker.
> (ENABLE_STATIC_PIE): New AC_DEFINE.
> (enable-static-pie): New LIBC_CONFIG_VAR.
> * configure: Regenerated.
> * csu/libc-start.c (LIBC_START_MAIN): Call _dl_relocate_static_pie
> in libc.a.
> * csu/libc-tls.c (__libc_setup_tls): Add main_map->l_addr to
> initimage.
> * elf/dl-support.c: Include "dynamic-link.h" and don't include
> "get-dynamic-info.h" for --enable-static-pie.
> (_dl_relocate_static_pie): New function for --enable-static-pie.
> (STATIC_PIE_BOOTSTRAP): New for --enable-static-pie.
> (RESOLVE_MAP): Likewise.
> * elf/dynamic-link.h (ELF_DURING_STARTUP): Also check
> STATIC_PIE_BOOTSTRAP.
> * elf/get-dynamic-info.h (elf_get_dynamic_info): Likewise.
> * sysdeps/generic/ldsodefs.h (_dl_relocate_static_pie): New.
> * sysdeps/x86_64/configure.ac: Check if linker supports static PIE.
> * sysdeps/x86_64/configure: Regenerated.
> ---
> Makeconfig | 20 ++++++++++--
> config.h.in | 3 ++
> configure | 78 +++++++++++++++++++++++++++++++++++++++++++++
> configure.ac | 29 +++++++++++++++++
> csu/libc-start.c | 2 ++
> csu/libc-tls.c | 6 ++--
> elf/dl-support.c | 39 +++++++++++++++++++++--
> elf/dynamic-link.h | 2 +-
> elf/get-dynamic-info.h | 6 ++--
> sysdeps/generic/ldsodefs.h | 7 ++++
> sysdeps/x86_64/configure | 33 +++++++++++++++++++
> sysdeps/x86_64/configure.ac | 22 +++++++++++++
> 12 files changed, 237 insertions(+), 10 deletions(-)
>
> diff --git a/Makeconfig b/Makeconfig
> index b51904b797..b45209fe5f 100644
> --- a/Makeconfig
> +++ b/Makeconfig
> @@ -386,6 +386,16 @@ LDFLAGS.so += $(hashstyle-LDFLAGS)
> LDFLAGS-rtld += $(hashstyle-LDFLAGS)
> endif
>
> +ifeq (yes,$(enable-static-pie))
> +pic-default = -DPIC
> +pie-default = $(pie-ccflag)
> +ifeq (yes,$(have-static-pie))
> +default-pie-ldflag = -static-pie
> +else
> +default-pie-ldflag = -Wl,-pie,--no-dynamic-linker,--eh-frame-hdr,-z,text
> +endif
> +endif
> +
> # If lazy relocations are disabled, add the -z now flag. Use
> # LDFLAGS-lib.so instead of LDFLAGS.so, to avoid adding the flag to
> # test modules.
> @@ -435,6 +445,7 @@ endif
> # Command for statically linking programs with the C library.
> ifndef +link-static
> +link-static-before-libc = $(CC) -nostdlib -nostartfiles -static -o $@ \
> + $(default-pie-ldflag) \
> $(sysdep-LDFLAGS) $(LDFLAGS) $(LDFLAGS-$(@F)) \
> $(addprefix $(csu-objpfx),$(static-start-installed-name)) \
> $(+preinit) $(+prectorT) \
> @@ -651,8 +662,13 @@ endif
> +prectorS = `$(CC) $(sysdep-LDFLAGS) --print-file-name=crtbeginS.o`
> +postctorS = `$(CC) $(sysdep-LDFLAGS) --print-file-name=crtendS.o`
> # Variants of the two previous definitions for statically linking programs.
> +ifeq (yes,$(enable-static-pie))
> ++prectorT = $(+prectorS)
> ++postctorT = $(+postctorS)
> +else
> +prectorT = `$(CC) $(sysdep-LDFLAGS) --print-file-name=crtbeginT.o`
> +postctorT = `$(CC) $(sysdep-LDFLAGS) --print-file-name=crtend.o`
> +endif
> csu-objpfx = $(common-objpfx)csu/
> elf-objpfx = $(common-objpfx)elf/
>
> @@ -973,7 +989,7 @@ libtypes = $(foreach o,$(object-suffixes-for-libc),$(libtype$o))
> all-object-suffixes := .o .os .oS
> object-suffixes :=
> CPPFLAGS-.o = $(pic-default)
> -CFLAGS-.o = $(filter %frame-pointer,$(+cflags))
> +CFLAGS-.o = $(filter %frame-pointer,$(+cflags)) $(pie-default)
> libtype.o := lib%.a
> object-suffixes += .o
> ifeq (yes,$(build-shared))
> @@ -998,7 +1014,7 @@ ifeq (yes,$(build-profile))
> all-object-suffixes += .op
> object-suffixes += .op
> CPPFLAGS-.op = -DPROF $(pic-default)
> -CFLAGS-.op = -pg
> +CFLAGS-.op = -pg $(pie-default)
> libtype.op = lib%_p.a
> endif
>
> diff --git a/config.h.in b/config.h.in
> index 014fb4ea0e..26ed7865ef 100644
> --- a/config.h.in
> +++ b/config.h.in
> @@ -236,6 +236,9 @@
> /* Build glibc with tunables support. */
> #define HAVE_TUNABLES 0
>
> +/* Define if static PIE is enabled. */
> +#define ENABLE_STATIC_PIE 0
> +
> /* Some compiler options may now allow to use ebp in __asm__ (used mainly
> in i386 6 argument syscall issue). */
> #define CAN_USE_REGISTER_ASM_EBP 0
> diff --git a/configure b/configure
> index 5cb5210107..a04c59bacd 100755
> --- a/configure
> +++ b/configure
> @@ -767,6 +767,7 @@ with_default_link
> enable_sanity_checks
> enable_shared
> enable_profile
> +enable_static_pie
> enable_timezone_tools
> enable_hardcoded_path_in_tests
> enable_stackguard_randomization
> @@ -1424,6 +1425,7 @@ Optional Features:
> in special situations) [default=yes]
> --enable-shared build shared library [default=yes if GNU ld]
> --enable-profile build profiled library [default=no]
> + --enable-static-pie build static executables as PIE [default=no]
> --disable-timezone-tools
> do not install timezone tools [default=install]
> --enable-hardcoded-path-in-tests
> @@ -3372,6 +3374,13 @@ else
> profile=no
> fi
>
> +# Check whether --enable-static-pie was given.
> +if test "${enable_static_pie+set}" = set; then :
> + enableval=$enable_static_pie; static_pie=$enableval
> +else
> + static_pie=no
> +fi
> +
> # Check whether --enable-timezone-tools was given.
> if test "${enable_timezone_tools+set}" = set; then :
> enableval=$enable_timezone_tools; enable_timezone_tools=$enableval
> @@ -5994,6 +6003,62 @@ fi
> $as_echo "$libc_linker_feature" >&6; }
>
>
> +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for linker that supports --no-dynamic-linker" >&5
> +$as_echo_n "checking for linker that supports --no-dynamic-linker... " >&6; }
> +libc_linker_feature=no
> +if test x"$gnu_ld" = x"yes"; then
> + libc_linker_check=`$LD -v --help 2>/dev/null | grep "\--no-dynamic-linker"`
> + if test -n "$libc_linker_check"; then
> + cat > conftest.c <<EOF
> +int _start (void) { return 42; }
> +EOF
> + if { ac_try='${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS $no_ssp
> + -Wl,--no-dynamic-linker -nostdlib -nostartfiles
> + -fPIC -shared -o conftest.so conftest.c
> + 1>&5'
> + { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
> + (eval $ac_try) 2>&5
> + ac_status=$?
> + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
> + test $ac_status = 0; }; }
> + then
> + libc_linker_feature=yes
> + fi
> + rm -f conftest*
> + fi
> +fi
> +if test $libc_linker_feature = yes; then
> + libc_cv_no_dynamic_linker=yes
> +else
> + libc_cv_no_dynamic_linker=no
> +fi
> +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_linker_feature" >&5
> +$as_echo "$libc_linker_feature" >&6; }
> +config_vars="$config_vars
> +have-no-dynamic-linker = $libc_cv_no_dynamic_linker"
> +
> +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for -static-pie" >&5
> +$as_echo_n "checking for -static-pie... " >&6; }
> +if ${libc_cv_static_pie+:} false; then :
> + $as_echo_n "(cached) " >&6
> +else
> + if { ac_try='${CC-cc} -static-pie -xc /dev/null -S -o /dev/null'
> + { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
> + (eval $ac_try) 2>&5
> + ac_status=$?
> + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
> + test $ac_status = 0; }; }; then :
> + libc_cv_static_pie=yes
> +else
> + libc_cv_static_pie=no
> +fi
> +
> +fi
> +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_static_pie" >&5
> +$as_echo "$libc_cv_static_pie" >&6; }
> +config_vars="$config_vars
> +have-static-pie = $libc_cv_static_pie"
> +
> { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -fpie" >&5
> $as_echo_n "checking for -fpie... " >&6; }
> if ${libc_cv_fpie+:} false; then :
> @@ -6888,6 +6953,19 @@ fi
> $as_echo "$libc_cv_pie_default" >&6; }
>
>
> +if test "$static_pie" = yes; then
> + # The linker must support --no-dynamic-linker.
> + if test "$libc_cv_no_dynamic_linker" != yes; then
> + as_fn_error $? "linker support for --no-dynamic-linker needed" "$LINENO" 5
> + fi
> + # Default to PIE.
> + libc_cv_pie_default=yes
> + $as_echo "#define ENABLE_STATIC_PIE 1" >>confdefs.h
> +
> +fi
> +config_vars="$config_vars
> +enable-static-pie = $static_pie"
> +
>
>
>
> diff --git a/configure.ac b/configure.ac
> index 2c6308883c..96af835ce8 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -176,6 +176,11 @@ AC_ARG_ENABLE([profile],
> [build profiled library @<:@default=no@:>@]),
> [profile=$enableval],
> [profile=no])
> +AC_ARG_ENABLE([static-pie],
> + AC_HELP_STRING([--enable-static-pie],
> + [build static executables as PIE @<:@default=no@:>@]),
> + [static_pie=$enableval],
> + [static_pie=no])
> AC_ARG_ENABLE([timezone-tools],
> AC_HELP_STRING([--disable-timezone-tools],
> [do not install timezone tools @<:@default=install@:>@]),
> @@ -1460,6 +1465,19 @@ LIBC_LINKER_FEATURE([-z execstack], [-Wl,-z,execstack],
> [libc_cv_z_execstack=yes], [libc_cv_z_execstack=no])
> AC_SUBST(libc_cv_z_execstack)
>
> +LIBC_LINKER_FEATURE([--no-dynamic-linker],
> + [-Wl,--no-dynamic-linker],
> + [libc_cv_no_dynamic_linker=yes],
> + [libc_cv_no_dynamic_linker=no])
> +LIBC_CONFIG_VAR([have-no-dynamic-linker], [$libc_cv_no_dynamic_linker])
> +
> +AC_CACHE_CHECK(for -static-pie, libc_cv_static_pie, [dnl
> +LIBC_TRY_CC_OPTION([-static-pie],
> + [libc_cv_static_pie=yes],
> + [libc_cv_static_pie=no])
> +])
> +LIBC_CONFIG_VAR([have-static-pie], [$libc_cv_static_pie])
> +
> AC_CACHE_CHECK(for -fpie, libc_cv_fpie, [dnl
> LIBC_TRY_CC_OPTION([-fpie], [libc_cv_fpie=yes], [libc_cv_fpie=no])
> ])
> @@ -1962,6 +1980,17 @@ fi
> rm -f conftest.*])
> AC_SUBST(libc_cv_pie_default)
>
> +if test "$static_pie" = yes; then
> + # The linker must support --no-dynamic-linker.
> + if test "$libc_cv_no_dynamic_linker" != yes; then
> + AC_MSG_ERROR([linker support for --no-dynamic-linker needed])
> + fi
> + # Default to PIE.
> + libc_cv_pie_default=yes
> + AC_DEFINE(ENABLE_STATIC_PIE)
> +fi
> +LIBC_CONFIG_VAR([enable-static-pie], [$static_pie])
> +
> AC_SUBST(profile)
> AC_SUBST(static_nss)
>
> diff --git a/csu/libc-start.c b/csu/libc-start.c
> index 24c63be02f..34dd125260 100644
> --- a/csu/libc-start.c
> +++ b/csu/libc-start.c
> @@ -141,6 +141,8 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL),
> __libc_multiple_libcs = &_dl_starting_up && !_dl_starting_up;
>
> #ifndef SHARED
> + _dl_relocate_static_pie ();
> +
> char **ev = &argv[argc + 1];
>
> __environ = ev;
> diff --git a/csu/libc-tls.c b/csu/libc-tls.c
> index 00138eb43a..1f8ddaf543 100644
> --- a/csu/libc-tls.c
> +++ b/csu/libc-tls.c
> @@ -114,6 +114,8 @@ __libc_setup_tls (void)
> size_t tcb_offset;
> const ElfW(Phdr) *phdr;
>
> + struct link_map *main_map = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
> +
> /* Look through the TLS segment if there is any. */
> if (_dl_phdr != NULL)
> for (phdr = _dl_phdr; phdr < &_dl_phdr[_dl_phnum]; ++phdr)
> @@ -122,7 +124,7 @@ __libc_setup_tls (void)
> /* Remember the values we need. */
> memsz = phdr->p_memsz;
> filesz = phdr->p_filesz;
> - initimage = (void *) phdr->p_vaddr;
> + initimage = (void *) phdr->p_vaddr + main_map->l_addr;
> align = phdr->p_align;
> if (phdr->p_align > max_align)
> max_align = phdr->p_align;
> @@ -163,8 +165,6 @@ __libc_setup_tls (void)
> _dl_static_dtv[0].counter = (sizeof (_dl_static_dtv) / sizeof (_dl_static_dtv[0])) - 2;
> // _dl_static_dtv[1].counter = 0; would be needed if not already done
>
> - struct link_map *main_map = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
> -
> /* Initialize the TLS block. */
> #if TLS_TCB_AT_TP
> _dl_static_dtv[2].pointer.val = ((char *) tlsblock + tcb_offset
> diff --git a/elf/dl-support.c b/elf/dl-support.c
> index 48340f7959..09b2229d48 100644
> --- a/elf/dl-support.c
> +++ b/elf/dl-support.c
> @@ -26,7 +26,11 @@
> #include <sys/param.h>
> #include <stdint.h>
> #include <ldsodefs.h>
> -#include <dl-machine.h>
> +#if ENABLE_STATIC_PIE
> +# include "dynamic-link.h"
> +#else
> +# include <dl-machine.h>
> +#endif
> #include <libc-lock.h>
> #include <dl-cache.h>
> #include <dl-librecon.h>
> @@ -199,7 +203,9 @@ const ElfW(Ehdr) *_dl_sysinfo_dso;
>
> struct link_map *_dl_sysinfo_map;
>
> -# include "get-dynamic-info.h"
> +# if !ENABLE_STATIC_PIE
> +# include "get-dynamic-info.h"
> +# endif
> #endif
> #include "setup-vdso.h"
>
> @@ -303,6 +309,35 @@ _dl_aux_init (ElfW(auxv_t) *av)
> }
> #endif
>
> +#if ENABLE_STATIC_PIE
> +/* Relocate static executable with PIE. */
> +
> +void
> +_dl_relocate_static_pie (void)
> +{
> +# define STATIC_PIE_BOOTSTRAP
> +# define RESOLVE_MAP(sym, version, flags) (&_dl_main_map)
> +# include "dynamic-link.h"
> +
> + /* Figure out the run-time load addres of static PIE. */
> + _dl_main_map.l_addr = elf_machine_load_address ();
> +
> + /* Read our own dynamic section and fill in the info array. */
> + _dl_main_map.l_ld = ((void *) _dl_main_map.l_addr
> + + elf_machine_dynamic ());
> + elf_get_dynamic_info (&_dl_main_map, NULL);
> +
> +# ifdef ELF_MACHINE_BEFORE_RTLD_RELOC
> + ELF_MACHINE_BEFORE_RTLD_RELOC (_dl_main_map.l_info);
> +# endif
> +
> + /* Relocate ourselves so we can do normal function calls and
> + data access using the global offset table. */
> + ELF_DYNAMIC_RELOCATE (&_dl_main_map, 0, 0, 0);
> + _dl_main_map.l_relocated = 1;
> +}
> +#endif
> +
>
> void
> internal_function
> diff --git a/elf/dynamic-link.h b/elf/dynamic-link.h
> index 60f2d91151..d3935f7da7 100644
> --- a/elf/dynamic-link.h
> +++ b/elf/dynamic-link.h
> @@ -95,7 +95,7 @@ elf_machine_lazy_rel (struct link_map *map,
>
> #ifdef RESOLVE_MAP
>
> -# ifdef RTLD_BOOTSTRAP
> +# if defined RTLD_BOOTSTRAP || defined STATIC_PIE_BOOTSTRAP
> # define ELF_DURING_STARTUP (1)
> # else
> # define ELF_DURING_STARTUP (0)
> diff --git a/elf/get-dynamic-info.h b/elf/get-dynamic-info.h
> index 7525c3a5b2..eb26d23649 100644
> --- a/elf/get-dynamic-info.h
> +++ b/elf/get-dynamic-info.h
> @@ -38,7 +38,7 @@ elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp)
> typedef Elf64_Xword d_tag_utype;
> #endif
>
> -#ifndef RTLD_BOOTSTRAP
> +#if !defined RTLD_BOOTSTRAP && !defined STATIC_PIE_BOOTSTRAP
> if (dyn == NULL)
> return;
> #endif
> @@ -139,9 +139,11 @@ elf_get_dynamic_info (struct link_map *l, ElfW(Dyn) *temp)
> /* Only the bind now flags are allowed. */
> assert (info[VERSYMIDX (DT_FLAGS_1)] == NULL
> || (info[VERSYMIDX (DT_FLAGS_1)]->d_un.d_val & ~DF_1_NOW) == 0);
> + /* Flags must not be set for ld.so. */
> assert (info[DT_FLAGS] == NULL
> || (info[DT_FLAGS]->d_un.d_val & ~DF_BIND_NOW) == 0);
> - /* Flags must not be set for ld.so. */
> +#endif
> +#if defined RTLD_BOOTSTRAP || defined STATIC_PIE_BOOTSTRAP
> assert (info[DT_RUNPATH] == NULL);
> assert (info[DT_RPATH] == NULL);
> #else
> diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
> index 49e673dd24..83791103cf 100644
> --- a/sysdeps/generic/ldsodefs.h
> +++ b/sysdeps/generic/ldsodefs.h
> @@ -1069,6 +1069,13 @@ extern void _dl_determine_tlsoffset (void) internal_function attribute_hidden;
> stack protector, among other things). */
> void __libc_setup_tls (void);
>
> +# if ENABLE_STATIC_PIE
> +/* Relocate static executable with PIE. */
> +void _dl_relocate_static_pie (void) attribute_hidden;
> +# else
> +# define _dl_relocate_static_pie()
> +# endif
> +
> /* Initialization of libpthread for statically linked applications.
> If libpthread is not linked in, this is an empty function. */
> void __pthread_initialize_minimal (void) weak_function;
> diff --git a/sysdeps/x86_64/configure b/sysdeps/x86_64/configure
> index efef46b1b7..8ee15b8a25 100644
> --- a/sysdeps/x86_64/configure
> +++ b/sysdeps/x86_64/configure
> @@ -85,6 +85,39 @@ if test x"$build_mathvec" = xnotset; then
> build_mathvec=yes
> fi
>
> +if test "$static_pie" = yes; then
> + { $as_echo "$as_me:${as_lineno-$LINENO}: checking for linker static PIE support" >&5
> +$as_echo_n "checking for linker static PIE support... " >&6; }
> +if ${libc_cv_ld_static_pie+:} false; then :
> + $as_echo_n "(cached) " >&6
> +else
> + cat > conftest.s <<\EOF
> + .text
> + .global _start
> + .weak foo
> +_start:
> + leaq foo(%rip), %rax
> +EOF
> + libc_cv_pie_option="-Wl,-pie"
> + if { ac_try='${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp $libc_cv_pie_option conftest.s 1>&5'
> + { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
> + (eval $ac_try) 2>&5
> + ac_status=$?
> + $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
> + test $ac_status = 0; }; }; then
> + libc_cv_ld_static_pie=yes
> + else
> + libc_cv_ld_static_pie=no
> + fi
> +rm -f conftest*
> +fi
> +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_ld_static_pie" >&5
> +$as_echo "$libc_cv_ld_static_pie" >&6; }
> + if test "$libc_cv_ld_static_pie" != yes; then
> + as_fn_error $? "linker support for static PIE needed" "$LINENO" 5
> + fi
> +fi
> +
> $as_echo "#define PI_STATIC_AND_HIDDEN 1" >>confdefs.h
>
>
> diff --git a/sysdeps/x86_64/configure.ac b/sysdeps/x86_64/configure.ac
> index fa86e953ee..c2d7cf3e61 100644
> --- a/sysdeps/x86_64/configure.ac
> +++ b/sysdeps/x86_64/configure.ac
> @@ -44,6 +44,28 @@ if test x"$build_mathvec" = xnotset; then
> build_mathvec=yes
> fi
>
> +dnl Check if linker supports static PIE.
> +if test "$static_pie" = yes; then
> + AC_CACHE_CHECK(for linker static PIE support, libc_cv_ld_static_pie, [dnl
> +cat > conftest.s <<\EOF
> + .text
> + .global _start
> + .weak foo
> +_start:
> + leaq foo(%rip), %rax
> +EOF
> + libc_cv_pie_option="-Wl,-pie"
> + if AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -nostartfiles -nostdlib $no_ssp $libc_cv_pie_option conftest.s 1>&AS_MESSAGE_LOG_FD); then
> + libc_cv_ld_static_pie=yes
> + else
> + libc_cv_ld_static_pie=no
> + fi
> +rm -f conftest*])
> + if test "$libc_cv_ld_static_pie" != yes; then
> + AC_MSG_ERROR([linker support for static PIE needed])
> + fi
> +fi
> +
> dnl It is always possible to access static and hidden symbols in an
> dnl position independent way.
> AC_DEFINE(PI_STATIC_AND_HIDDEN)
> --
> 2.13.5
>
Any comments?
--
H.J.