[svn-r20504] Purpose:

    General shared library improvements for CYGWIN / AIX

Description:

    Shared libraries are disabled on both CYGWIN and AIX due
    to inability to build them correctly. Part of the problem
    in both of these situations is the lack of the libtool
    flag -no-undefined, which tells libtool that all needed
    symbols are defined at link time (a requirement on these
    systems) and that it's okay to build shared libraries.

    Another problem are lack of dependencies between wrapper
    libraries and core C HDF5 library.

    This patch addresses both of these by fixing configure to
    add in -no-undefined flag for libtool during linking and
    adds automake dependencies in the Makefile.am files.

    After testing, both CYGWIN and AIX now generate shared
    libraries, but there are still some test failures in each.
    (cache_api, dt_arith, and testerror.sh on CYGWIN, and
    fortran tests on AIX).

    Even though the shared libraries are not quite perfect,
    this is a general improvement to what we had before, so
    I'm applying the patch anyways. Note that default behavior
    of shared libraries on these systems being disabled has
    NOT been changed and requires the use of the
    --enable-unsupported to attempt to build them.

    We will need to address the test failures in each
    architecture prior to formally supporting shared
    libraries on each.

Tested:

    h5committested & CYGWIN tested (on bangan)
    (AIX tested by Albert on bp-login2)

1 files changed, 28 insertions, 0 deletions

diff --git a/configure.in b/configure.in
index 9941744..42b552f 100644
--- a/configure.in
+++ b/configure.in
@@ -95,6 +95,7 @@ AC_SUBST([H5_CFLAGS])
 AC_SUBST([H5_CPPFLAGS])
 AC_SUBST([H5_FCFLAGS])
 AC_SUBST([H5_CXXFLAGS])
+AC_SUBST([H5_LDFLAGS])
 
 dnl AM_CFLAGS (and company) are for CFLAGS that should be used on HDF5,
 dnl and WILL be exported to h5cc (or h5fc, etc) if set by configure.
@@ -953,6 +954,11 @@ if test "X${ALLOW_UNSUPPORTED}" != "Xyes"; then
 fi
 
 dnl ----------------------------------------------------------------------
+dnl Windows won't create DLLs without the following macro.
+dnl
+AC_LIBTOOL_WIN32_DLL
+
+dnl ----------------------------------------------------------------------
 dnl Create libtool.  If shared/static libraries are going to be enabled
 dnl or disabled, it should happen before these macros.
 AC_LIBTOOL_DLOPEN
@@ -1243,6 +1249,27 @@ case "$host" in
 esac
 
 dnl ----------------------------------------------------------------------
+dnl Some platforms require that all symbols are resolved when a library
+dnl is linked. We can use the -no-undefined flag to tell libtool that
+dnl it will be able to build shared libraries on these architectures,
+dnl as it will not do so by default.
+dnl
+if test "X${enable_shared}" = "Xyes"; then
+  AC_MSG_CHECKING([if libtool needs -no-undefined flag to build shared libraries])
+  case "`uname`" in
+    CYGWIN*|MINGW*|AIX*)
+      dnl Add in the -no-undefined flag to LDFLAGS for libtool.
+      AC_MSG_RESULT([yes])
+      H5_LDFLAGS="$H5_LDFLAGS -no-undefined"
+      ;;
+    *)
+      dnl Don't add in anything.
+      AC_MSG_RESULT([no])
+      ;;
+  esac
+fi
+
+dnl ----------------------------------------------------------------------
 dnl Test for Largefile support.
 dnl
 AC_MSG_CHECKING([if configure should try to set up large file support])
@@ -4392,6 +4419,7 @@ AC_CONFIG_FILES([src/libhdf5.settings
                  hl/fortran/examples/run-hlfortran-ex.sh])
 
 AC_OUTPUT
+LT_OUTPUT
 no_create=$saved_no_create
 
 # Then the stamp2 file for H5config.h