Add --enable-default-pie option to GCC configurehjl/pie/gcc-4_9-branch

Add --enable-default-pie option to configure GCC to generate PIE by
default.

gcc/

2015-03-06  Magnus Granberg  <zorry@gentoo.org>
	    H.J. Lu  <hongjiu.lu@intel.com>

	* Makefile.in (COMPILER): Add @NO_PIE_CFLAGS@.
	(BUILD_CFLAGS): Likewise.
	(BUILD_CXXFLAGS): Likewise.
	(LINKER): Add @NO_PIE_FLAG@.
	(BUILD_LDFLAGS): Likewise.
	(libgcc.mvars): Set NO_PIE_CFLAGS to -fno-PIE for
	--enable-default-pie.
	* common.opt (fPIE): Initialize to -1.
	(fpie): Likewise.
	(no-pie): New option.
	(pie): Replace "Negative(shared)" with "Negative(no-pie)".
	* configure.ac: Add --enable-default-pie.
	(NO_PIE_CFLAGS): New.  Check if -fno-PIE works.  AC_SUBST.
	(NO_PIE_FLAG): New.  Check if -no-pie works.  AC_SUBST.
	* defaults.h (DEFAULT_FLAG_PIE): New.  Default PIE to -fPIE.
	* gcc.c (NO_PIE_SPEC): New.
	(PIE_SPEC): Likewise.
	(LD_PIE_SPEC): Likewise.
	(LINK_PIE_SPEC): Handle -no-pie.  Use PIE_SPEC and LD_PIE_SPEC.
	* opts.c (DEFAULT_FLAG_PIE): New.  Set to 0 if ENABLE_DEFAULT_PIE
	is undefined.
	(finish_options): Update opts->x_flag_pie if it is -1.
	* config/gnu-user.h (FVTABLE_VERIFY_SPEC): New.
	(GNU_USER_TARGET_STARTFILE_SPEC): Use FVTABLE_VERIFY_SPEC.  Use
	PIE_SPEC and NO_PIE_SPEC if ENABLE_DEFAULT_PIE is defined.
	(GNU_USER_TARGET_STARTFILE_SPEC): Use FVTABLE_VERIFY_SPEC.
	* doc/install.texi: Document --enable-default-pie.
	* doc/invoke.texi: Document -no-pie.
	* config.in: Regenerated.
	* configure: Likewise.

gcc/ada/

2015-03-06  H.J. Lu  <hongjiu.lu@intel.com>

	* gcc-interface/Makefile.in (TOOLS_LIBS): Add @NO_PIE_FLAG@.

libgcc/

2015-03-06  H.J. Lu  <hongjiu.lu@intel.com>

	* Makefile.in (CRTSTUFF_CFLAGS): Add $(NO_PIE_CFLAGS).

13 files changed, 204 insertions, 16 deletions

diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index b47733cef50..bf07f83f4cb 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -237,6 +237,12 @@ LINKER = $(CC)
 LINKER_FLAGS = $(CFLAGS)
 endif
 
+# We don't want to compile the compiler with -fPIE, it make PCH fail.
+COMPILER += @NO_PIE_CFLAGS@
+
+# Link with -no-pie since we compile the compiler with -fno-PIE.
+LINKER += @NO_PIE_FLAG@
+
 # Like LINKER, but use a mutex for serializing front end links.
 ifeq (@DO_LINK_MUTEX@,true)
 LLINKER = $(SHELL) $(srcdir)/lock-and-run.sh linkfe.lck $(LINKER)
@@ -750,6 +756,8 @@ CC_FOR_BUILD = @CC_FOR_BUILD@
 CXX_FOR_BUILD = @CXX_FOR_BUILD@
 BUILD_CFLAGS= @BUILD_CFLAGS@ -DGENERATOR_FILE
 BUILD_CXXFLAGS = @BUILD_CXXFLAGS@ -DGENERATOR_FILE
+BUILD_CFLAGS += @NO_PIE_CFLAGS@
+BUILD_CXXFLAGS += @NO_PIE_CFLAGS@
 
 # Native compiler that we use.  This may be C++ some day.
 COMPILER_FOR_BUILD = $(CXX_FOR_BUILD)
@@ -761,6 +769,7 @@ BUILD_LINKERFLAGS = $(BUILD_CXXFLAGS)
 
 # Native linker and preprocessor flags.  For x-fragment overrides.
 BUILD_LDFLAGS=@BUILD_LDFLAGS@
+BUILD_LDFLAGS += @NO_PIE_FLAG@
 BUILD_CPPFLAGS= -I. -I$(@D) -I$(srcdir) -I$(srcdir)/$(@D) \
 		-I$(srcdir)/../include @INCINTL@ $(CPPINC) $(CPPFLAGS)
 
@@ -1819,6 +1828,12 @@ libgcc.mvars: config.status Makefile specs xgcc$(exeext)
 	echo GCC_CFLAGS = '$(GCC_CFLAGS)' >> tmp-libgcc.mvars
 	echo INHIBIT_LIBC_CFLAGS = '$(INHIBIT_LIBC_CFLAGS)' >> tmp-libgcc.mvars
 	echo TARGET_SYSTEM_ROOT = '$(TARGET_SYSTEM_ROOT)' >> tmp-libgcc.mvars
+	if test @enable_default_pie@ = yes; then \
+	  NO_PIE_CFLAGS="-fno-PIE"; \
+	else \
+	  NO_PIE_CFLAGS=; \
+	fi; \
+	echo NO_PIE_CFLAGS = "$$NO_PIE_CFLAGS" >> tmp-libgcc.mvars
 
 	mv tmp-libgcc.mvars libgcc.mvars
 
diff --git a/gcc/ada/gcc-interface/Makefile.in b/gcc/ada/gcc-interface/Makefile.in
index e2cc4a9e0ec..8437150933e 100644
--- a/gcc/ada/gcc-interface/Makefile.in
+++ b/gcc/ada/gcc-interface/Makefile.in
@@ -266,6 +266,9 @@ TOOLS_LIBS = ../link.o ../targext.o ../../ggc-none.o ../../libcommon-target.a \
   ../../libcommon.a ../../../libcpp/libcpp.a $(LIBGNAT) $(LIBINTL) $(LIBICONV) \
   ../$(LIBBACKTRACE) ../$(LIBIBERTY) $(SYSLIBS) $(TGT_LIB)
 
+# Add -no-pie to TOOLS_LIBS since some of them are compiled with -fno-PIE.
+TOOLS_LIBS += @NO_PIE_FLAG@
+
 # Specify the directories to be searched for header files.
 # Both . and srcdir are used, in that order,
 # so that tm.h and config.h will be found in the compilation
diff --git a/gcc/common.opt b/gcc/common.opt
index 51ddd77c9a9..e1e4afd835d 100644
--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -1648,7 +1648,7 @@ Common Report Var(flag_pic,2) Negative(fPIE)
 Generate position-independent code if possible (large mode)
 
 fPIE
-Common Report Var(flag_pie,2) Negative(fpic)
+Common Report Var(flag_pie,2) Negative(fpic) Init(-1)
 Generate position-independent code for executables if possible (large mode)
 
 fpic
@@ -1656,7 +1656,7 @@ Common Report Var(flag_pic,1) Negative(fpie)
 Generate position-independent code if possible (small mode)
 
 fpie
-Common Report Var(flag_pie,1) Negative(fPIC)
+Common Report Var(flag_pie,1) Negative(fPIC) Init(-1)
 Generate position-independent code for executables if possible (small mode)
 
 fplugin=
@@ -2687,8 +2687,12 @@ Driver
 symbolic
 Driver
 
-pie
+no-pie
 Driver RejectNegative Negative(shared)
+Don't create a position independent executable
+
+pie
+Driver RejectNegative Negative(no-pie)
 Create a position independent executable
 
 z
diff --git a/gcc/config.in b/gcc/config.in
index de4f09017f4..de829604baf 100644
--- a/gcc/config.in
+++ b/gcc/config.in
@@ -65,6 +65,12 @@
 #endif
 
 
+/* Define if your target supports default PIE and it is enabled. */
+#ifndef USED_FOR_TARGET
+#undef ENABLE_DEFAULT_PIE
+#endif
+
+
 /* Define if you want more run-time sanity checks for dataflow. */
 #ifndef USED_FOR_TARGET
 #undef ENABLE_DF_CHECKING
diff --git a/gcc/config/gnu-user.h b/gcc/config/gnu-user.h
index 9b466212009..4a0f0b7ef77 100644
--- a/gcc/config/gnu-user.h
+++ b/gcc/config/gnu-user.h
@@ -41,19 +41,29 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
    object constructed before entering `main'.  */
 
 #if defined HAVE_LD_PIE
-#define GNU_USER_TARGET_STARTFILE_SPEC \
-  "%{!shared: %{pg|p|profile:gcrt1.o%s;pie:Scrt1.o%s;:crt1.o%s}} \
-   crti.o%s %{static:crtbeginT.o%s;shared|pie:crtbeginS.o%s;:crtbegin.o%s} \
-   %{fvtable-verify=none:%s; \
+#define FVTABLE_VERIFY_SPEC \
+  "%{fvtable-verify=none:%s; \
      fvtable-verify=preinit:vtv_start_preinit.o%s; \
      fvtable-verify=std:vtv_start.o%s}"
+#if defined ENABLE_DEFAULT_PIE
+#define GNU_USER_TARGET_STARTFILE_SPEC \
+  "%{!shared: %{pg|p|profile:gcrt1.o%s;: \
+    %{" PIE_SPEC ":Scrt1.o%s} %{" NO_PIE_SPEC ":crt1.o%s}}} \
+   crti.o%s %{static:crtbeginT.o%s;: %{shared:crtbeginS.o%s} \
+	      %{" PIE_SPEC ":crtbeginS.o%s} \
+	      %{" NO_PIE_SPEC ":crtbegin.o%s}}" \
+   FVTABLE_VERIFY_SPEC
+#else
+#define GNU_USER_TARGET_STARTFILE_SPEC \
+  "%{!shared: %{pg|p|profile:gcrt1.o%s;pie:Scrt1.o%s;:crt1.o%s}} \
+   crti.o%s %{static:crtbeginT.o%s;shared|pie:crtbeginS.o%s;:crtbegin.o%s}" \
+   FVTABLE_VERIFY_SPEC
+#endif
 #else
 #define GNU_USER_TARGET_STARTFILE_SPEC \
   "%{!shared: %{pg|p|profile:gcrt1.o%s;:crt1.o%s}} \
-   crti.o%s %{static:crtbeginT.o%s;shared|pie:crtbeginS.o%s;:crtbegin.o%s} \
-   %{fvtable-verify=none:%s; \
-     fvtable-verify=preinit:vtv_start_preinit.o%s; \
-     fvtable-verify=std:vtv_start.o%s}"
+   crti.o%s %{static:crtbeginT.o%s;shared|pie:crtbeginS.o%s;:crtbegin.o%s}" \
+   FVTABLE_VERIFY_SPEC
 #endif
 #undef  STARTFILE_SPEC
 #define STARTFILE_SPEC GNU_USER_TARGET_STARTFILE_SPEC
diff --git a/gcc/configure b/gcc/configure
index fbfbdbb53ed..ff911531e60 100755
--- a/gcc/configure
+++ b/gcc/configure
@@ -600,6 +600,9 @@ ac_includes_default="\
 
 ac_subst_vars='LTLIBOBJS
 LIBOBJS
+NO_PIE_FLAG
+NO_PIE_CFLAGS
+enable_default_pie
 PICFLAG
 enable_host_shared
 enable_plugin
@@ -933,6 +936,7 @@ enable_plugin
 enable_host_shared
 enable_libquadmath_support
 with_linker_hash_style
+enable_default_pie
 '
       ac_precious_vars='build_alias
 host_alias
@@ -1661,6 +1665,7 @@ Optional Features:
   --enable-host-shared    build host code as shared libraries
   --disable-libquadmath-support
                           disable libquadmath support for Fortran
+  --enable-default-pie    enable Position Independent Executable as default
 
 Optional Packages:
   --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
@@ -17936,7 +17941,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 17939 "configure"
+#line 17944 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -18042,7 +18047,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 18045 "configure"
+#line 18050 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -28170,6 +28175,76 @@ _ACEOF
 
 fi
 
+# 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; enable_default_pie=$enableval
+else
+  enable_default_pie=no
+fi
+
+if test x$enable_default_pie == xyes ; then
+
+$as_echo "#define ENABLE_DEFAULT_PIE 1" >>confdefs.h
+
+fi
+
+
+# Check if -fno-PIE works.
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for -fno-PIE option" >&5
+$as_echo_n "checking for -fno-PIE option... " >&6; }
+if test "${gcc_cv_c_no_fpie+set}" = set; then :
+  $as_echo_n "(cached) " >&6
+else
+  saved_CFLAGS="$CFLAGS"
+   CFLAGS="$CFLAGS -fno-PIE"
+   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+int main(void) {return 0;}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  gcc_cv_c_no_fpie=yes
+else
+  gcc_cv_c_no_fpie=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+   CFLAGS="$saved_CFLAGS"
+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
+$as_echo_n "checking for -no-pie option... " >&6; }
+if test "${gcc_cv_no_pie+set}" = set; then :
+  $as_echo_n "(cached) " >&6
+else
+  saved_LDFLAGS="$LDFLAGS"
+   LDFLAGS="$LDFLAGS -no-pie"
+   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+int main(void) {return 0;}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+  gcc_cv_no_pie=yes
+else
+  gcc_cv_no_pie=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+   LDFLAGS="$saved_LDFLAGS"
+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"
+fi
+
+
 # Configure the subdirectories
 # AC_CONFIG_SUBDIRS($subdirs)
 
diff --git a/gcc/configure.ac b/gcc/configure.ac
index 792e9bb3d65..8786630876b 100644
--- a/gcc/configure.ac
+++ b/gcc/configure.ac
@@ -5677,6 +5677,46 @@ if test x"${LINKER_HASH_STYLE}" != x; then
                                          [The linker hash style])
 fi
 
+# Check whether --enable-default-pie was given.
+AC_ARG_ENABLE(default-pie,
+[AS_HELP_STRING([--enable-default-pie],
+  [enable Position Independent Executable as default])],
+enable_default_pie=$enableval,
+enable_default_pie=no)
+if test x$enable_default_pie == xyes ; then
+  AC_DEFINE(ENABLE_DEFAULT_PIE, 1,
+      [Define if your target supports default PIE and it is enabled.])
+fi
+AC_SUBST([enable_default_pie])
+
+# Check if -fno-PIE works.
+AC_CACHE_CHECK([for -fno-PIE option],
+  [gcc_cv_c_no_fpie],
+  [saved_CFLAGS="$CFLAGS"
+   CFLAGS="$CFLAGS -fno-PIE"
+   AC_COMPILE_IFELSE([int main(void) {return 0;}],
+     [gcc_cv_c_no_fpie=yes],
+     [gcc_cv_c_no_fpie=no])
+   CFLAGS="$saved_CFLAGS"])
+if test "$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],
+  [gcc_cv_no_pie],
+  [saved_LDFLAGS="$LDFLAGS"
+   LDFLAGS="$LDFLAGS -no-pie"
+   AC_LINK_IFELSE([int main(void) {return 0;}],
+     [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"
+fi
+AC_SUBST([NO_PIE_FLAG])
+
 # Configure the subdirectories
 # AC_CONFIG_SUBDIRS($subdirs)
 
diff --git a/gcc/defaults.h b/gcc/defaults.h
index f94ae17a7fe..2b893229310 100644
--- a/gcc/defaults.h
+++ b/gcc/defaults.h
@@ -1223,6 +1223,12 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #define DEFAULT_PCC_STRUCT_RETURN 1
 #endif
 
+/* Default PIE to -fPIE.  */
+#ifndef DEFAULT_FLAG_PIE
+# define DEFAULT_FLAG_PIE 2
+#endif
+
+
 #ifdef GCC_INSN_FLAGS_H
 /* Dependent default target macro definitions
 
diff --git a/gcc/doc/install.texi b/gcc/doc/install.texi
index 1daedff69bf..60507e9b2f3 100644
--- a/gcc/doc/install.texi
+++ b/gcc/doc/install.texi
@@ -1459,6 +1459,9 @@ not be built.
 Specify that the run-time libraries for stack smashing protection
 should not be built.
 
+@item --enable-default-pie
+Turn on @option{-fPIE} and @option{-pie} by default.
+
 @item --disable-libquadmath
 Specify that the GCC quad-precision math library should not be built.
 On some systems, the library is required to be linkable when building
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index dddc4d9a230..e4d14669343 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -10360,6 +10360,10 @@ For predictable results, you must also specify the same set of options
 used for compilation (@option{-fpie}, @option{-fPIE},
 or model suboptions) when you specify this linker option.
 
+@item -no-pie
+@opindex no-pie
+Don't produce a position independent executable.
+
 @item -rdynamic
 @opindex rdynamic
 Pass the flag @option{-export-dynamic} to the ELF linker, on targets
diff --git a/gcc/gcc.c b/gcc/gcc.c
index c7ce64d8fc8..d441b39cce0 100644
--- a/gcc/gcc.c
+++ b/gcc/gcc.c
@@ -676,12 +676,20 @@ proper position among the other output files.  */
 #endif
 #endif
 
+#ifdef ENABLE_DEFAULT_PIE
+#define NO_PIE_SPEC	"no-pie|static"
+#define PIE_SPEC	NO_PIE_SPEC "|r|shared:;"
+#else
+#define PIE_SPEC "pie"
+#endif
+
 #ifndef LINK_PIE_SPEC
 #ifdef HAVE_LD_PIE
-#define LINK_PIE_SPEC "%{pie:-pie} "
+#define LD_PIE_SPEC "-pie"
 #else
-#define LINK_PIE_SPEC "%{pie:} "
+#define LD_PIE_SPEC ""
 #endif
+#define LINK_PIE_SPEC "%{no-pie:} " "%{" PIE_SPEC ":" LD_PIE_SPEC "} "
 #endif
 
 #ifndef LINK_BUILDID_SPEC
diff --git a/gcc/opts.c b/gcc/opts.c
index fbdebd79b1e..0f632f976fd 100644
--- a/gcc/opts.c
+++ b/gcc/opts.c
@@ -714,8 +714,22 @@ finish_options (struct gcc_options *opts, struct gcc_options *opts_set,
       opts->x_flag_section_anchors = 0;
     }
 
+#ifndef ENABLE_DEFAULT_PIE
+#undef DEFAULT_FLAG_PIE
+#define DEFAULT_FLAG_PIE 0
+#endif
+
   if (!opts->x_flag_opts_finished)
     {
+      /* We initialize opts->x_flag_pie to -1 so that targets can set a
+	 default value.  */
+      if (opts->x_flag_pie == -1)
+	{
+	  if (opts->x_flag_pic == 0)
+	    opts->x_flag_pie = DEFAULT_FLAG_PIE;
+	  else
+	    opts->x_flag_pie = 0;
+	}
       if (opts->x_flag_pie)
 	opts->x_flag_pic = opts->x_flag_pie;
       if (opts->x_flag_pic && !opts->x_flag_pie)
diff --git a/libgcc/Makefile.in b/libgcc/Makefile.in
index e86e98de476..2875c6ea060 100644
--- a/libgcc/Makefile.in
+++ b/libgcc/Makefile.in
@@ -281,7 +281,7 @@ INTERNAL_CFLAGS = $(CFLAGS) $(LIBGCC2_CFLAGS) $(HOST_LIBGCC2_CFLAGS) \
 
 # Options to use when compiling crtbegin/end.
 CRTSTUFF_CFLAGS = -O2 $(GCC_CFLAGS) $(INCLUDES) $(MULTILIB_CFLAGS) -g0 \
-  -finhibit-size-directive -fno-inline -fno-exceptions \
+  $(NO_PIE_CFLAGS) -finhibit-size-directive -fno-inline -fno-exceptions \
   -fno-zero-initialized-in-bss -fno-toplevel-reorder -fno-tree-vectorize \
   -fno-stack-protector \
   $(INHIBIT_LIBC_CFLAGS)