* _inttypes_h.m4 (gl_INTTYPES_H): Use AC_CHECK_DECLS_ONCE with only one argument, for Autoconf 2.60. * fileblocks.m4 (gl_PREREQ_FILEBLOCKS): AC_CHECK_DECLS_ONCE may expand to nothing, so add a shell command to avoid syntax error. * getpass.m4 (gl_PREREQ_GETPASS): Likewise.