Add configure flag to enable gnu hash style by default.

ld/
	* configure.ac: Add --enable-default-hash-style option.
	* ldmain.c (main): Set link_info.emit_hash to DEFAULT_EMIT_SYSV_HASH.
	Set link_info.emit_gnu_hash to DEFAULT_EMIT_GNU_HASH.
	* configure: Regenerate.
	* config.in: Regenerate.

gold/
	* configure.ac: Add --enable-default-hash-style option.
	* options.h (hash_style): Use DEFAULT_HASH_STYLE as default value.
	* configure: Regenerate.
	* config.in: Regenerate.

5 files changed, 96 insertions, 3 deletions

diff --git a/ld/ChangeLog b/ld/ChangeLog
index 9af0eeb..645c0fe 100644
--- a/ld/ChangeLog
+++ b/ld/ChangeLog
@@ -1,3 +1,12 @@
+2017-08-08  Romain Geissler  <romain.geissler@gmail.com>
+	    Alan Modra  <amodra@gmail.com>
+
+	* configure.ac: Add --enable-default-hash-style option.
+	* ldmain.c (main): Set link_info.emit_hash to DEFAULT_EMIT_SYSV_HASH.
+	Set link_info.emit_gnu_hash to DEFAULT_EMIT_GNU_HASH.
+	* configure: Regenerate.
+	* config.in: Regenerate.
+
 2017-08-08  Alan Modra  <amodra@gmail.com>
 
 	* testsuite/ld-aarch64/ifunc-1-local.d: Run ld with --hash-style=sysv.
diff --git a/ld/config.in b/ld/config.in
index 5d91380..a846743 100644
--- a/ld/config.in
+++ b/ld/config.in
@@ -7,6 +7,12 @@
 #endif
 #define __CONFIG_H__ 1
 
+/* Define to 1 if you want to emit gnu hash in the ELF linker by default. */
+#undef DEFAULT_EMIT_GNU_HASH
+
+/* Define to 1 if you want to emit sysv hash in the ELF linker by default. */
+#undef DEFAULT_EMIT_SYSV_HASH
+
 /* Define if you want compressed debug sections by default. */
 #undef DEFAULT_FLAG_COMPRESS_DEBUG
 
diff --git a/ld/configure b/ld/configure
index 640902b..de709d3 100755
--- a/ld/configure
+++ b/ld/configure
@@ -790,6 +790,7 @@ enable_got
 enable_compressed_debug_sections
 enable_new_dtags
 enable_relro
+enable_default_hash_style
 enable_werror
 enable_build_warnings
 enable_nls
@@ -1450,6 +1451,8 @@ Optional Features:
                           compress debug sections by default]
   --enable-new-dtags      set DT_RUNPATH instead of DT_RPATH by default]
   --enable-relro          enable -z relro in ELF linker by default
+  --enable-default-hash-style={sysv,gnu,both}
+                          use this default hash style
   --enable-werror         treat compile warnings as errors
   --enable-build-warnings enable build-time compiler warnings
   --disable-nls           do not use Native Language Support
@@ -11722,7 +11725,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11725 "configure"
+#line 11728 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11828,7 +11831,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11831 "configure"
+#line 11834 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -15564,6 +15567,34 @@ if test "${enable_relro+set}" = set; then :
 esac
 fi
 
+# Decide which "--hash-style" to use by default
+# Provide a configure time option to override our default.
+# Check whether --enable-default-hash-style was given.
+if test "${enable_default_hash_style+set}" = set; then :
+  enableval=$enable_default_hash_style; case "${enable_default_hash_style}" in
+  sysv | gnu | both) ;;
+  *) as_fn_error "bad value ${enable_default_hash_style} for enable-default-hash-style option" "$LINENO" 5 ;;
+esac
+else
+  case "${target}" in
+  # Enable gnu hash only on GNU targets, but not mips
+  mips*-*-*) enable_default_hash_style=sysv ;;
+  *-*-gnu* | *-*-linux* | *-*-nacl*) enable_default_hash_style=both ;;
+  *) enable_default_hash_style=sysv ;;
+esac
+fi
+
+
+case "${enable_default_hash_style}" in
+  sysv | both) ac_default_emit_sysv_hash=1 ;;
+  *) ac_default_emit_sysv_hash=0 ;;
+esac
+
+case "${enable_default_hash_style}" in
+  gnu | both) ac_default_emit_gnu_hash=1 ;;
+  *) ac_default_emit_gnu_hash=0 ;;
+esac
+
 
 # Set the 'development' global.
 . $srcdir/../bfd/development.sh
@@ -17228,6 +17259,18 @@ _ACEOF
 
 
 
+cat >>confdefs.h <<_ACEOF
+#define DEFAULT_EMIT_SYSV_HASH $ac_default_emit_sysv_hash
+_ACEOF
+
+
+
+cat >>confdefs.h <<_ACEOF
+#define DEFAULT_EMIT_GNU_HASH $ac_default_emit_gnu_hash
+_ACEOF
+
+
+
 
 
 
diff --git a/ld/configure.ac b/ld/configure.ac
index ffe8018..99d127b 100644
--- a/ld/configure.ac
+++ b/ld/configure.ac
@@ -177,6 +177,32 @@ AC_ARG_ENABLE(relro,
   no)  ac_default_ld_z_relro=0 ;;
 esac])dnl
 
+# Decide which "--hash-style" to use by default
+# Provide a configure time option to override our default.
+AC_ARG_ENABLE([default-hash-style],
+AS_HELP_STRING([--enable-default-hash-style={sysv,gnu,both}],
+	       [use this default hash style]),
+[case "${enable_default_hash_style}" in
+  sysv | gnu | both) ;;
+  *) AC_MSG_ERROR([bad value ${enable_default_hash_style} for enable-default-hash-style option]) ;;
+esac],
+[case "${target}" in
+  # Enable gnu hash only on GNU targets, but not mips
+  mips*-*-*) enable_default_hash_style=sysv ;;
+  *-*-gnu* | *-*-linux* | *-*-nacl*) enable_default_hash_style=both ;;
+  *) enable_default_hash_style=sysv ;;
+esac])
+
+case "${enable_default_hash_style}" in
+  sysv | both) ac_default_emit_sysv_hash=1 ;;
+  *) ac_default_emit_sysv_hash=0 ;;
+esac
+
+case "${enable_default_hash_style}" in
+  gnu | both) ac_default_emit_gnu_hash=1 ;;
+  *) ac_default_emit_gnu_hash=0 ;;
+esac
+
 AM_BINUTILS_WARNINGS
 
 AM_LC_MESSAGES
@@ -408,6 +434,14 @@ AC_DEFINE_UNQUOTED(DEFAULT_LD_Z_RELRO,
   $ac_default_ld_z_relro,
   [Define to 1 if you want to enable -z relro in ELF linker by default.])
 
+AC_DEFINE_UNQUOTED([DEFAULT_EMIT_SYSV_HASH],
+  [$ac_default_emit_sysv_hash],
+  [Define to 1 if you want to emit sysv hash in the ELF linker by default.])
+
+AC_DEFINE_UNQUOTED([DEFAULT_EMIT_GNU_HASH],
+  [$ac_default_emit_gnu_hash],
+  [Define to 1 if you want to emit gnu hash in the ELF linker by default.])
+
 AC_SUBST(elf_list_options)
 AC_SUBST(elf_shlib_list_options)
 AC_SUBST(elf_plt_unwind_list_options)
diff --git a/ld/ldmain.c b/ld/ldmain.c
index cb1e2d1..2b09f20 100644
--- a/ld/ldmain.c
+++ b/ld/ldmain.c
@@ -273,7 +273,8 @@ main (int argc, char **argv)
   link_info.keep_memory = TRUE;
   link_info.combreloc = TRUE;
   link_info.strip_discarded = TRUE;
-  link_info.emit_hash = TRUE;
+  link_info.emit_hash = DEFAULT_EMIT_SYSV_HASH;
+  link_info.emit_gnu_hash = DEFAULT_EMIT_GNU_HASH;
   link_info.callbacks = &link_callbacks;
   link_info.input_bfds_tail = &link_info.input_bfds;
   /* SVR4 linkers seem to set DT_INIT and DT_FINI based on magic _init