Non-host system configuration for linker plugins.

* configure.ac (--enable-linker-plugin-configure-flags)
	(--enable-linker-plugin-flags): New flags.
	(configdirs): Conditionally add libiberty-linker-plugin.
	* configure: Regenerate.
	* Makefile.def (host_modules): Add libiberty-linker-plugin.
	(host_modules) <lto-plugin>: Pay attention to
	@extra_linker_plugin_flags@ and
	@extra_linker_plugin_configure_flags@.
	(all-lto-plugin): Also depend on all-libiberty-linker-plugin.
	* Makefile.in: Regenerate.
	gcc/
	* doc/install.texi (--enable-linker-plugin-configure-flags)
	(--enable-linker-plugin-flags): Document new flags.

From-SVN: r211644

ChangeLog

@@ -1,5 +1,16 @@
 2014-06-13  Thomas Schwinge  <thomas@codesourcery.com>
 
+	* configure.ac (--enable-linker-plugin-configure-flags)
+	(--enable-linker-plugin-flags): New flags.
+	(configdirs): Conditionally add libiberty-linker-plugin.
+	* configure: Regenerate.
+	* Makefile.def (host_modules): Add libiberty-linker-plugin.
+	(host_modules) <lto-plugin>: Pay attention to
+	@extra_linker_plugin_flags@ and
+	@extra_linker_plugin_configure_flags@.
+	(all-lto-plugin): Also depend on all-libiberty-linker-plugin.
+	* Makefile.in: Regenerate.
+
 	* Makefile.tpl (configure-[+prefix+][+module+])
 	(configure-stage[+id+]-[+prefix+][+module+]): If specified, use
 	"module_srcdir" instead of "module" for locating a module's srcdir.

Makefile.def

@@ -85,6 +85,14 @@ host_modules= { module= libdecnumber; bootstrap=true; };
 host_modules= { module= libgui; };
 host_modules= { module= libiberty; bootstrap=true;
 	        extra_configure_flags='@extra_host_libiberty_configure_flags@';};
+// Linker plugins may need their own build of libiberty; see
+// gcc/doc/install.texi.  We take care that this build of libiberty doesn't get
+// installed.  It's a helper library for linker plugins, so we pay attention to
+// @extra_linker_plugin_flags@ and @extra_linker_plugin_configure_flags@.
+host_modules= { module= libiberty-linker-plugin; bootstrap=true;
+		module_srcdir=libiberty;
+	        extra_configure_flags='@extra_host_libiberty_configure_flags@ --disable-install-libiberty @extra_linker_plugin_flags@ @extra_linker_plugin_configure_flags@';
+		extra_make_flags='@extra_linker_plugin_flags@'; };
 // We abuse missing to avoid installing anything for libiconv.
 host_modules= { module= libiconv;
 		extra_configure_flags='--disable-shared';
@@ -111,7 +119,8 @@ host_modules= { module= libtermcap; no_check=true;
 host_modules= { module= utils; no_check=true; };
 host_modules= { module= gnattools; };
 host_modules= { module= lto-plugin; bootstrap=true;
-		extra_configure_flags=--enable-shared; };
+		extra_configure_flags='--enable-shared @extra_linker_plugin_flags@ @extra_linker_plugin_configure_flags@';
+		extra_make_flags='@extra_linker_plugin_flags@'; };
 
 target_modules = { module= libstdc++-v3;
 		   bootstrap=true;
@@ -338,7 +347,10 @@ dependencies = { module=all-fixincludes; on=all-libiberty; };
 dependencies = { module=all-gnattools; on=all-target-libada; };
 dependencies = { module=all-gnattools; on=all-target-libstdc++-v3; };
 
+// Depending on the specific configuration, the LTO plugin will either use the
+// generic libiberty build or the specific build for linker plugins.
 dependencies = { module=all-lto-plugin; on=all-libiberty; };
+dependencies = { module=all-lto-plugin; on=all-libiberty-linker-plugin; };
 
 dependencies = { module=all-utils; on=all-libiberty; };
 

configure

@@ -644,6 +644,8 @@ DEBUG_PREFIX_CFLAGS_FOR_TARGET
 SYSROOT_CFLAGS_FOR_TARGET
 stage1_languages
 extra_host_libiberty_configure_flags
+extra_linker_plugin_flags
+extra_linker_plugin_configure_flags
 clooginc
 clooglibs
 islinc
@@ -778,6 +780,8 @@ with_cloog_include
 with_cloog_lib
 enable_cloog_version_check
 enable_lto
+enable_linker_plugin_configure_flags
+enable_linker_plugin_flags
 enable_stage1_languages
 enable_objc_gc
 with_build_sysroot
@@ -1477,6 +1481,12 @@ Optional Features:
   --disable-cloog-version-check
                           disable check for CLooG version
   --enable-lto            enable link time optimization support
+  --enable-linker-plugin-configure-flags=FLAGS
+                          additional flags for configuring linker plugins
+                          [none]
+  --enable-linker-plugin-flags=FLAGS
+                          additional flags for configuring and building linker
+                          plugins [none]
   --enable-stage1-languages[=all]
                           choose additional languages to build during stage1.
                           Mostly useful for compiler development
@@ -6302,6 +6312,23 @@ else
 fi
 
 
+# Check whether --enable-linker-plugin-configure-flags was given.
+if test "${enable_linker_plugin_configure_flags+set}" = set; then :
+  enableval=$enable_linker_plugin_configure_flags; extra_linker_plugin_configure_flags=$enableval
+else
+  extra_linker_plugin_configure_flags=
+fi
+
+
+# Check whether --enable-linker-plugin-flags was given.
+if test "${enable_linker_plugin_flags+set}" = set; then :
+  enableval=$enable_linker_plugin_flags; extra_linker_plugin_flags=$enableval
+else
+  extra_linker_plugin_flags=
+fi
+
+
+
 
 # By default, C and C++ are the only stage 1 languages.
 stage1_languages=,c,
@@ -6712,6 +6739,21 @@ for i in ${target_configdirs_all} ; do
   fi
 done
 
+# libiberty-linker-plugin is special: it doesn't have its own source directory,
+# so we have to add it after the preceding checks.
+if test x"$extra_linker_plugin_flags$extra_linker_plugin_configure_flags" != x
+then
+  case " $configdirs " in
+    *" libiberty "*)
+      # If we can build libiberty, we can also build libiberty-linker-plugin.
+      configdirs="$configdirs libiberty-linker-plugin"
+      extra_linker_plugin_configure_flags="$extra_linker_plugin_configure_flags \
+        --with-libiberty=../libiberty-linker-plugin";;
+    *)
+      as_fn_error "libiberty missing" "$LINENO" 5;;
+  esac
+fi
+
 # Produce a warning message for the subdirs we can't configure.
 # This isn't especially interesting in the Cygnus tree, but in the individual
 # FSF releases, it's important to let people know when their machine isn't

configure.ac

@@ -1731,6 +1731,19 @@ ACX_ELF_TARGET_IFELSE([# ELF platforms build the lto-plugin always.
   esac
 ])
 
+AC_ARG_ENABLE(linker-plugin-configure-flags,
+  [AS_HELP_STRING([[--enable-linker-plugin-configure-flags=FLAGS]],
+    [additional flags for configuring linker plugins @<:@none@:>@])],
+  extra_linker_plugin_configure_flags=$enableval,
+  extra_linker_plugin_configure_flags=)
+AC_SUBST(extra_linker_plugin_configure_flags)
+AC_ARG_ENABLE(linker-plugin-flags,
+  [AS_HELP_STRING([[--enable-linker-plugin-flags=FLAGS]],
+    [additional flags for configuring and building linker plugins @<:@none@:>@])],
+  extra_linker_plugin_flags=$enableval,
+  extra_linker_plugin_flags=)
+AC_SUBST(extra_linker_plugin_flags)
+
 
 # By default, C and C++ are the only stage 1 languages.
 stage1_languages=,c,
@@ -2141,6 +2154,21 @@ for i in ${target_configdirs_all} ; do
   fi
 done
 
+# libiberty-linker-plugin is special: it doesn't have its own source directory,
+# so we have to add it after the preceding checks.
+if test x"$extra_linker_plugin_flags$extra_linker_plugin_configure_flags" != x
+then
+  case " $configdirs " in
+    *" libiberty "*)
+      # If we can build libiberty, we can also build libiberty-linker-plugin.
+      configdirs="$configdirs libiberty-linker-plugin"
+      extra_linker_plugin_configure_flags="$extra_linker_plugin_configure_flags \
+        --with-libiberty=../libiberty-linker-plugin";;
+    *)
+      AC_MSG_ERROR([libiberty missing]);;
+  esac
+fi
+
 # Produce a warning message for the subdirs we can't configure.
 # This isn't especially interesting in the Cygnus tree, but in the individual
 # FSF releases, it's important to let people know when their machine isn't

gcc/ChangeLog

@@ -1,3 +1,8 @@
+2014-06-13  Thomas Schwinge  <thomas@codesourcery.com>
+
+	* doc/install.texi (--enable-linker-plugin-configure-flags)
+	(--enable-linker-plugin-flags): Document new flags.
+
 2014-06-13  Martin Jambor  <mjambor@suse.cz>
 
 	PR ipa/61186

gcc/doc/install.texi

@@ -1780,6 +1780,25 @@ GLIBC 2.11 or above, otherwise disabled.
 Enable support for link-time optimization (LTO).  This is enabled by
 default, and may be disabled using @option{--disable-lto}.
 
+@item --enable-linker-plugin-configure-flags=FLAGS
+@itemx --enable-linker-plugin-flags=FLAGS
+By default, linker plugins (such as the LTO plugin) are built for the
+host system architecture.  For the case that the linker has a
+different (but run-time compatible) architecture, these flags can be
+specified to build plugins that are compatible to the linker.  For
+example, if you are building GCC for a 64-bit x86_64
+(@samp{x86_64-unknown-linux-gnu}) host system, but have a 32-bit x86
+GNU/Linux (@samp{i686-pc-linux-gnu}) linker executable (which is
+executable on the former system), you can configure GCC as follows for
+getting compatible linker plugins:
+
+@smallexample
+% @var{srcdir}/configure \
+    --host=x86_64-unknown-linux-gnu \
+    --enable-linker-plugin-configure-flags=--host=i686-pc-linux-gnu \
+    --enable-linker-plugin-flags='CC=gcc\ -m32\ -Wl,-rpath,[...]/i686-pc-linux-gnu/lib'
+@end smallexample
+
 @item --with-plugin-ld=@var{pathname}
 Enable an alternate linker to be used at link-time optimization (LTO)
 link time when @option{-fuse-linker-plugin} is enabled.