Copy include/config.h to include/my_config.h at configure-time. Also,

continue to update it at make-time.

One shouldn't need to run "make" on server source to get the stuff we say
plugins should use.

configure.in

@@ -2815,6 +2815,7 @@ AC_CONFIG_FILES(Makefile extra/Makefile mysys/Makefile dnl
  include/mysql_version.h plugin/Makefile win/Makefile)
 
 AC_CONFIG_COMMANDS([default], , test -z "$CONFIG_HEADERS" || echo timestamp > stamp-h)
+AC_CONFIG_COMMANDS([my_config.h], cp include/config.h include/my_config.h)
 
 # Ensure that table handlers gets all modifications to CFLAGS/CXXFLAGS
 AC_CONFIG_COMMANDS_POST(ac_configure_args="$ac_configure_args CFLAGS='$CFLAGS' CXXFLAGS='$CXXFLAGS'")

include/Makefile.am

@@ -15,9 +15,8 @@
 # Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 # MA 02111-1307, USA
 
-BUILT_SOURCES =		$(HEADERS_GEN_MAKE) link_sources
-HEADERS_GEN_CONFIGURE =		mysql_version.h
-HEADERS_GEN_MAKE =		my_config.h
+BUILT_SOURCES =		link_sources
+HEADERS_GEN_CONFIGURE =		mysql_version.h my_config.h
 HEADERS_ABI =		mysql.h mysql_com.h mysql_time.h \
 			my_list.h my_alloc.h typelib.h mysql/plugin.h
 pkginclude_HEADERS =	$(HEADERS_ABI) my_dbug.h m_string.h my_sys.h \
@@ -26,8 +25,7 @@ pkginclude_HEADERS =	$(HEADERS_ABI) my_dbug.h m_string.h my_sys.h \
 			decimal.h errmsg.h my_global.h my_net.h \
 			my_getopt.h sslopt-longopts.h my_dir.h \
 			sslopt-vars.h sslopt-case.h sql_common.h keycache.h \
-			m_ctype.h my_attribute.h $(HEADERS_GEN_CONFIGURE) \
-			$(HEADERS_GEN_MAKE)
+			m_ctype.h my_attribute.h $(HEADERS_GEN_CONFIGURE)
 
 noinst_HEADERS =	config-win.h config-netware.h my_bit.h \
 			heap.h my_bitmap.h my_uctype.h \