Patch: Gcj: add -static-libgcj option for linking.

[David Daney <ddaney at avtrex dot com>]

This patch adds an option '-static-libgcj' that causes libgcj to be 
linked statically instead of dynamically.  This is similar to the 
-static-libgcc option.

The main reason one would do this is to save space.  The minimal Hello 
World program statically linked is about 8MB.  libgcj.so.7.0.0 is around 
23MB.

I should note that this option is not for everyone as many parts of 
libgcj do not work with static linking.  But if you are careful, and 
play a few tricks, it can be quite useful.

Tested with make -k check in libjava on i686-pc-linux-gnu with no failures.

OK to commit?

gcc:
2006-03-06  David Daney  <ddaney@avtrex.com>

	* java/gcj.texi: Document -static-libgcj option.

libjava:
2006-03-06  David Daney  <ddaney@avtrex.com>

	* configure.ac (LD): Add AC_CHECK_TOOL for ld.
	* configure: Regenerated.
	(LD_START_STATIC_SPEC): New AC_SUBST, set with ld check.
	(LD_FINISH_STATIC_SPEC): Ditto
	* libgcj.spec.in: Wrap -lgcj in LD_START_STATIC_SPEC and
	LD_FINISH_STATIC_SPEC.


Index: libjava/libgcj.spec.in
===================================================================
--- libjava/libgcj.spec.in	(revision 111728)
+++ libjava/libgcj.spec.in	(working copy)
@@ -4,6 +4,6 @@
 # to link with libgcj.
 #
 %rename lib liborig
-*lib: -lgcj -lm @LIBICONV@ @GCSPEC@ @THREADSPEC@ @ZLIBSPEC@ @SYSTEMSPEC@ %(libgcc) %(liborig)
+*lib: @LD_START_STATIC_SPEC@ -lgcj @LD_FINISH_STATIC_SPEC@ -lm @LIBICONV@ @GCSPEC@ @THREADSPEC@ @ZLIBSPEC@ @SYSTEMSPEC@ %(libgcc) %(liborig)
 
 *jc1: @HASH_SYNC_SPEC@ @DIVIDESPEC@ @CHECKREFSPEC@ @JC1GCSPEC@ @EXCEPTIONSPEC@ @BACKTRACESPEC@ @IEEESPEC@ -fkeep-inline-functions
Index: libjava/configure.ac
===================================================================
--- libjava/configure.ac	(revision 111728)
+++ libjava/configure.ac	(working copy)
@@ -113,6 +113,7 @@
 AM_INIT_AUTOMAKE([1.9.0])
 
 AC_CHECK_TOOL(AS, as)
+AC_CHECK_TOOL(LD, ld)
 AC_CHECK_TOOL(AR, ar)
 AC_CHECK_TOOL(RANLIB, ranlib, :)
 
@@ -1418,6 +1419,17 @@
 # See if we support thread-local storage.
 GCC_CHECK_TLS
 
+# Check if linker supports static linking on a per library basis
+LD_START_STATIC_SPEC=
+LD_FINISH_STATIC_SPEC=
+if $LD --help 2>&1 | grep -q -e -call_shared ; then
+  if $LD --help 2>&1 | grep -q -e -non_shared ; then
+    LD_START_STATIC_SPEC='%{static-libgcj:-non_shared}'
+    LD_FINISH_STATIC_SPEC='%{static-libgcj:-call_shared}'
+  fi
+fi
+AC_SUBST(LD_START_STATIC_SPEC)
+AC_SUBST(LD_FINISH_STATIC_SPEC)
 
 here=`${PWDCMD-pwd}`
 AC_SUBST(here)
Index: gcc/java/gcj.texi
===================================================================
--- gcc/java/gcj.texi	(revision 111728)
+++ gcc/java/gcj.texi	(working copy)
@@ -420,6 +420,15 @@
 of the @code{gij} command.
 
 This option is an alternative to using @code{--main}; you cannot use both.
+
+@item -static-libgcj
+This option causes linking to be done against a static version of the
+libgcj runtime library.  This option is only available if
+corresponding linker support exists.
+
+Important Note: Static linking of libgcj may cause essential (to your
+program) parts of libgcj to be omitted.  Caution must be used when
+using this option.
 @end table
 
 @node Code Generation