Modified plugins/Makefile.am to add -no-undefined as required on cygwin.

configure.ac

@@ -1195,7 +1195,7 @@ if test "x$enable_hdf5" = xyes; then
    # See if H5Dread_chunk is available
    AC_SEARCH_LIBS([H5Dread_chunk],[hdf5_hldll hdf5_hl], [has_readchunks=yes], [has_readdhunks=no])
 
-   # See if hdf5 library supports Read-Only S3 (byte-range) driver 
+   # See if hdf5 library supports Read-Only S3 (byte-range) driver
    AC_SEARCH_LIBS([H5Pset_fapl_ros3],[hdf5_hldll hdf5_hl], [has_ros3=yes], [has_ros3=no])
    if test "x$has_ros3" = xyes; then
     AC_DEFINE([ENABLE_HDF5_ROS3], [1], [if true, support byte-range using hdf5 virtual file driver.])
@@ -1476,6 +1476,7 @@ AC_MSG_RESULT([$BINFILE_NAME $FC $CXX])
 # Bugfix for Cygwin.
 ##
 AC_MSG_CHECKING([if libtool needs -no-undefined flag to build shared libraries])
+NOUNDEFINED=""
 case "`uname`" in
      CYGWIN*|MINGW*|AIX*)
      ## Add in the -no-undefined flag to LDFLAGS for libtool.

plugins/Makefile.am

@@ -5,7 +5,7 @@
 include $(top_srcdir)/lib_flags.am
 
 AM_LDFLAGS += -module -avoid-version -shared -export-dynamic	\
- -rpath ${abs_builddir}
+ -rpath ${abs_builddir} ${NOUNDEFINED}
 
 BZIP2HDRS = bzlib.h bzlib_private.h
 BZIP2SRC = blocksort.c huffman.c crctable.c randtable.c compress.c decompress.c bzlib.c