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, 59 insertions, 1 deletions

diff --git a/gold/ChangeLog b/gold/ChangeLog
index 950be70..813b27f 100644
--- a/gold/ChangeLog
+++ b/gold/ChangeLog
@@ -1,3 +1,11 @@
+2017-08-08  Romain Geissler  <romain.geissler@gmail.com>
+	    Alan Modra  <amodra@gmail.com>
+
+	* configure.ac: Add --enable-default-hash-style option.
+	* options.h (hash_style): Use DEFAULT_HASH_STYLE as default value.
+	* configure: Regenerate.
+	* config.in: Regenerate.
+
 2017-08-03  James Clarke  <jrtc27@jrtc27.com>
 
 	* options.h (General_options): Set a non-NULL second help string
diff --git a/gold/config.in b/gold/config.in
index d9f7b76..5855fca 100644
--- a/gold/config.in
+++ b/gold/config.in
@@ -10,6 +10,9 @@
 /* Define if building universal (internal helper macro) */
 #undef AC_APPLE_UNIVERSAL_BUILD
 
+/* Set the default --hash-style value */
+#undef DEFAULT_HASH_STYLE
+
 /* Define to 1 if you want to enable -z relro in ELF linker by default. */
 #undef DEFAULT_LD_Z_RELRO
 
diff --git a/gold/configure b/gold/configure
index cb020be..90a706d 100755
--- a/gold/configure
+++ b/gold/configure
@@ -797,6 +797,7 @@ enable_threads
 enable_plugins
 enable_relro
 enable_targets
+enable_default_hash_style
 with_lib_path
 enable_dependency_tracking
 enable_nls
@@ -1447,6 +1448,8 @@ Optional Features:
   --enable-plugins        linker plugins
   --enable-relro          enable -z relro in ELF linker by default
   --enable-targets        alternative target configurations
+  --enable-default-hash-style={sysv,gnu,both}
+                          use this default hash style
   --disable-dependency-tracking  speeds up one-time build
   --enable-dependency-tracking   do not reject slow dependency extractors
   --disable-nls           do not use Native Language Support
@@ -3410,6 +3413,30 @@ if test -n "$enable_targets"; then
   done
 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 "${target}" in
+  # Enable gnu hash only on GNU targets, but not mips
+  mips*-*-*) enable_default_hash_style=sysv ;;
+  *-*-gnu* | *-*-linux* | *-*-nacl*) enable_default_hash_style=both ;;
+  *) enable_default_hash_style=sysv ;;
+esac
+fi
+
+
+
+cat >>confdefs.h <<_ACEOF
+#define DEFAULT_HASH_STYLE "${enable_default_hash_style}"
+_ACEOF
+
+
 # See which specific instantiations we need.
 targetobjs=
 all_targets=
diff --git a/gold/configure.ac b/gold/configure.ac
index cbe3380..d7fa1f8 100644
--- a/gold/configure.ac
+++ b/gold/configure.ac
@@ -161,6 +161,26 @@ if test -n "$enable_targets"; then
   done
 fi
 
+# 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])
+
+AC_DEFINE_UNQUOTED([DEFAULT_HASH_STYLE],
+  ["${enable_default_hash_style}"],
+  [Set the default --hash-style value])
+
 # See which specific instantiations we need.
 targetobjs=
 all_targets=
diff --git a/gold/options.h b/gold/options.h
index 6b45f64..970e76f 100644
--- a/gold/options.h
+++ b/gold/options.h
@@ -925,7 +925,7 @@ class General_options
 		N_("Min fraction of empty buckets in dynamic hash"),
 		N_("FRACTION"));
 
-  DEFINE_enum(hash_style, options::TWO_DASHES, '\0', "sysv",
+  DEFINE_enum(hash_style, options::TWO_DASHES, '\0', DEFAULT_HASH_STYLE,
 	      N_("Dynamic hash style"), N_("[sysv,gnu,both]"),
 	      {"sysv", "gnu", "both"});