2010-09-20  Nathan Sidwell  <nathan@codesourcery.com>

	* configure.ac (enable-gnu-indirect-function): New configure
	option.  Verify glibc version.
	* configure: Rebuilt.

	testsuite/
	* lib/target-supports-dg.exp (dg-require_ifunc): Remove remnants
	of dg-require-alias.
	* lib/target-supports.exp (check_ifunc_available): Check known
	good GLIBC version.  Remove check_alias_available remnants.

Index: configure
===================================================================
--- configure	(revision 164430)
+++ configure	(working copy)
@@ -905,6 +905,7 @@
 enable_fast_install
 enable_libtool_lock
 with_plugin_ld
+enable_gnu_indirect_function
 enable_comdat
 enable_gnu_unique_object
 enable_linker_build_id
@@ -1611,6 +1612,8 @@
   --enable-fast-install[=PKGS]
                           optimize for fast installation [default=yes]
   --disable-libtool-lock  avoid locking (might break parallel builds)
+  --enable-gnu-indirect-function	enable the use of the @gnu_indirect_function to
+				glibc systems
   --enable-comdat         enable COMDAT group support
   --enable-gnu-unique-object	enable the use of the @gnu_unique_object ELF extension on
 				glibc systems
@@ -17139,7 +17142,7 @@
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 17142 "configure"
+#line 17145 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -17245,7 +17248,7 @@
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 17248 "configure"
+#line 17251 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -21332,19 +21335,27 @@
 # gnu_indirect_function type is an extension proposed at
 # http://groups.google/com/group/generic-abi/files. It allows dynamic runtime
 # selection of function implementation
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler for gnu_indirect_function" >&5
+# Check whether --enable-gnu-indirect-function was given.
+if test "${enable_gnu_indirect_function+set}" = set; then :
+  enableval=$enable_gnu_indirect_function; case $enable_gnu_indirect_function in
+    yes | no) ;;
+    *) as_fn_error "'$enable_gnu_indirect_function' is an invalid value for --enable-gnu-indirect-function.
+Valid choices are 'yes' and 'no'." "$LINENO" 5 ;;
+  esac
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: checking assembler for gnu_indirect_function" >&5
 $as_echo_n "checking assembler for gnu_indirect_function... " >&6; }
-if test "${gcc_cv_as_indirect_function+set}" = set; then :
+if test "${gcc_cv_as_gnu_indirect_function+set}" = set; then :
   $as_echo_n "(cached) " >&6
 else
-  gcc_cv_as_indirect_function=no
+  gcc_cv_as_gnu_indirect_function=no
     if test $in_tree_gas = yes; then
     if test $in_tree_gas_is_elf = yes \
-  && test $gcc_cv_gas_vers -ge `expr \( \( 2 \* 1000 \) + 20 \) \* 1000 + 1`
-  then gcc_cv_as_indirect_function=yes
+  && test $gcc_cv_gas_vers -ge `expr \( \( 2 \* 1000 \) + 20.1 \) \* 1000 + gcc_cv_as_gnu_indirect_function=yes`
+  then :
 fi
   elif test x$gcc_cv_as != x; then
-    echo '	.type  Foo, @gnu_indirect_function
+    echo '.type foo, @gnu_indirect_function
 Foo:' > conftest.s
     if { ac_try='$gcc_cv_as $gcc_cv_as_flags  -o conftest.o conftest.s >&5'
   { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
@@ -21353,7 +21364,7 @@
   $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; }
     then
-	gcc_cv_as_indirect_function=yes
+	gcc_cv_as_gnu_indirect_function=yes
     else
       echo "configure: failed program was" >&5
       cat conftest.s >&5
@@ -21361,16 +21372,29 @@
     rm -f conftest.o conftest.s
   fi
 fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $gcc_cv_as_indirect_function" >&5
-$as_echo "$gcc_cv_as_indirect_function" >&6; }
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $gcc_cv_as_gnu_indirect_function" >&5
+$as_echo "$gcc_cv_as_gnu_indirect_function" >&6; }
+if test $gcc_cv_as_gnu_indirect_function = yes; then
+  # Also check for ld.so support, i.e. glibc 2.11 or higher.
+   if test x$host = x$build -a x$host = x$target &&
+       glibcver=`ldd --version 2>/dev/null | sed 's/.* //;q'`; then
+      glibcmajor=`expr "$glibcver" : "\([0-9]*\)"`
+      glibcminor=`expr "$glibcver" : "[2-9]*\.\([0-9]*\)"`
+      glibcnum=`expr $glibcmajor \* 1000 + $glibcminor`
+      if test "$glibcnum" -ge 2011 ; then
+        enable_gnu_indirect_function=yes
+      fi
+    fi
+fi
+fi
 
+if test x$enable_gnu_indirect_function = xyes; then
 
-if test $gcc_cv_as_indirect_function = yes ; then
+$as_echo "#define HAVE_GAS_GNU_INDIRECT_FUNCTION 1" >>confdefs.h
 
-$as_echo "#define HAVE_GAS_INDIRECT_FUNCTION 1" >>confdefs.h
-
 fi
 
+
 if test $in_tree_ld != yes ; then
   ld_ver=`$gcc_cv_ld --version 2>/dev/null | sed 1q`
   if test x"$ld_is_gold" = xyes; then
Index: testsuite/lib/target-supports-dg.exp
===================================================================
--- testsuite/lib/target-supports-dg.exp	(revision 164430)
+++ testsuite/lib/target-supports-dg.exp	(working copy)
@@ -94,12 +94,7 @@
 # test.
 
 proc dg-require-ifunc { args } {
-    set ifunc_available [ check_ifunc_available ]
-    if { $ifunc_available == -1 } {
-	upvar name name
-	unresolved "$name"
-    }
-    if { $ifunc_available < 2 } {
+    if { ![ check_ifunc_available ] } {
 	upvar dg-do-what dg-do-what
 	set dg-do-what [list [lindex ${dg-do-what} 0] "N" "P"]
     }
Index: testsuite/lib/target-supports.exp
===================================================================
--- testsuite/lib/target-supports.exp	(revision 164430)
+++ testsuite/lib/target-supports.exp	(working copy)
@@ -372,12 +372,10 @@
 # proc check_ifunc_available { }
 ###############################
 
-# Determine if the target toolchain supports the alias attribute.
+# Determine if the target toolchain supports the ifunc attribute.
 
-# Returns 2 if the target supports aliases.  Returns 1 if the target
-# only supports weak aliased.  Returns 0 if the target does not
-# support aliases at all.  Returns -1 if support for aliases could not
-# be determined.
+# Returns 1 if the target supports ifunc.  Returns 0 if the target
+# does not support ifunc.
 
 proc check_ifunc_available { } {
     global ifunc_available_saved
@@ -390,26 +388,19 @@
 	set obj ifunc[pid].o
         verbose "check_ifunc_available  compiling testfile $src" 2
 	set f [open $src "w"]
-	# Compile a small test program.  The definition of "g" is
-	# necessary to keep the Solaris assembler from complaining
-	# about the program.
-	puts $f "#ifdef __cplusplus\nextern \"C\"\n#endif\n"
-	puts $f "void g() {} void f() __attribute__((ifunc(\"g\")));"
+	puts $f "#endif"
+	puts $f "#ifdef __cplusplus\nextern \"C\"\n#endif"
+	puts $f "void g() {}"
+	puts $f "void f() __attribute__((ifunc(\"g\")));"
 	close $f
 	set lines [${tool}_target_compile $src $obj object ""]
 	file delete $src
 	remote_file build delete $obj
 
 	if [string match "" $lines] then {
-	    # No error messages, everything is OK.
-	    set ifunc_available_saved 2
+	    set ifunc_available_saved 1
 	} else {
-	    if [regexp "ifunc is not supported" $lines] {
-		verbose "check_ifunc_available  target does not support ifunc" 2
-		set ifunc_available_saved 0
-	    } else {
-		set ifunc_available_saved -1
-	    }
+	    set ifunc_available_saved 0
 	}
 
 	verbose "check_ifunc_available  returning $ifunc_available_saved" 2
Index: configure.ac
===================================================================
--- configure.ac	(revision 164430)
+++ configure.ac	(working copy)
@@ -2161,16 +2161,34 @@
 # gnu_indirect_function type is an extension proposed at
 # http://groups.google/com/group/generic-abi/files. It allows dynamic runtime
 # selection of function implementation
-gcc_GAS_CHECK_FEATURE(gnu_indirect_function, gcc_cv_as_indirect_function,
- [elf,2,20,1],,
-[	.type  Foo, @gnu_indirect_function
-Foo:])
-GCC_TARGET_TEMPLATE([HAVE_GAS_INDIRECT_FUNCTION])
-if test $gcc_cv_as_indirect_function = yes ; then
-  AC_DEFINE(HAVE_GAS_INDIRECT_FUNCTION, 1,
-  [Define if your assembler supports indirect function type.])
+AC_ARG_ENABLE(gnu-indirect-function,
+ [  --enable-gnu-indirect-function	enable the use of the @gnu_indirect_function to
+				glibc systems],
+ [case $enable_gnu_indirect_function in
+    yes | no) ;;
+    *) AC_MSG_ERROR(['$enable_gnu_indirect_function' is an invalid value for --enable-gnu-indirect-function.
+Valid choices are 'yes' and 'no'.]) ;;
+  esac],
+ [gcc_GAS_CHECK_FEATURE([gnu_indirect_function], gcc_cv_as_gnu_indirect_function,
+   [elf,2,20.1],,
+   [.type foo, @gnu_indirect_function
+Foo:],,
+# Also check for ld.so support, i.e. glibc 2.11 or higher.
+   [[if test x$host = x$build -a x$host = x$target &&
+       glibcver=`ldd --version 2>/dev/null | sed 's/.* //;q'`; then
+      glibcmajor=`expr "$glibcver" : "\([0-9]*\)"`
+      glibcminor=`expr "$glibcver" : "[2-9]*\.\([0-9]*\)"`
+      glibcnum=`expr $glibcmajor \* 1000 + $glibcminor`
+      if test "$glibcnum" -ge 2011 ; then
+        enable_gnu_indirect_function=yes
+      fi
+    fi]])])
+if test x$enable_gnu_indirect_function = xyes; then
+  AC_DEFINE(HAVE_GAS_GNU_INDIRECT_FUNCTION, 1,
+   [Define if your assembler supports @gnu_indirect_function.])
 fi
 
+
 changequote(,)dnl
 if test $in_tree_ld != yes ; then
   ld_ver=`$gcc_cv_ld --version 2>/dev/null | sed 1q`
