+GNU tar exercises many features that can cause problems with older GCC
+versions. In particular, GCC 2.8.1 (sparc, -O1 or -O2) is known to
+miscompile GNU tar. No compiler-related problems have been reported
+when using GCC 2.95.2 or later.
+
+Recent versions of Solaris tar sport a new -E option to generate
+extended headers in an undocumented format. GNU tar does not
+understand these headers.
+
+* Static linking.
+
+Some platform will, by default, prepare a smaller `tar' executable
+which depends on shared libraries. Since GNU `tar' may be used for
+system-level backups and disaster recovery, installers might prefer to
+force static linking, making a bigger `tar' executable maybe, but able to
+work standalone, in situations where shared libraries are not available.
+The way to achieve static linking varies between systems. Set LDFLAGS
+to a value from the table below, before configuration (see `INSTALL').
+
+ Platform Compiler LDFLAGS
+
+ (any) Gnu C -static
+ AIX (vendor) -bnso -bI:/lib/syscalls.exp
+ HPUX (vendor) -Wl,-a,archive
+ IRIX (vendor) -non_shared
+ OSF (vendor) -non_shared
+ SCO 3.2v5 (vendor) -dn
+ Solaris (vendor) -Bstatic
+ SunOS (vendor) -Bstatic
+
+* Failed tests `ignfail.sh' or `incremen.sh'.
+
+In an NFS environment, lack of synchronization between machine clocks
+might create difficulties to any tool comparing dates and file time stamps,
+like `tar' in incremental dumps. This has been a recurrent problem with
+GNU Make for the last few years. We would like a general solution.
+
+* BSD compatibility matters.
+
+Set LIBS to `-lbsd' before configuration (see `INSTALL') if the linker
+complains about `bsd_ioctl' (Slackware). Also set CPPFLAGS to
+`-I/usr/include/bsd' if <sgtty.h> is not found (Slackware).
+
+* OPENStep 4.2 swap files
+
+Tar cannot read the file /private/vm/swapfile.front (even as root).
+This file is not a real file, but some kind of uncompressed view of
+the real compressed swap file; there is no reason to back it up, so
+the simplest workaround is to avoid tarring this file.
+
+
+Special topics
+--------------
+
+Here are a few special matters about GNU `tar', not related to build
+matters. See previous section for such.
+
+* File attributes.
+
+About *security*, it is probable that future releases of `tar' will have
+some behavior changed. There are many pending suggestions to choose from.
+Today, extracting an archive not being `root', `tar' will restore suid/sgid
+bits on files but owned by the extracting user. `root' automatically gets
+a lot of special privileges, `-p' might later become required to get them.
+
+GNU `tar' does not properly restore symlink attributes. Various systems
+implement flavors of symbolic links showing different behavior and
+properties. We did not successfully sorted all these out yet. Currently,
+the `lchown' call will be used if available, but that's all.
+
+* POSIX compliance.
+
+GNU `tar' implements an early draft of the POSIX 1003.1 `ustar' standard
+which is different from the final standard. This will be progressively
+corrected over the incoming few years. Don't be mislead by the mere
+existence of the --posix option. Later releases will become able to
+read truly POSIX archives, and also to produce them under option. (Also,
+if you look at the internals, don't take the GNU extensions you see for
+granted, as they are planned to change.) GNU tar 2.0 will produce POSIX
+archives by default, but there is a long way before we get there.
+
+* What's next?
+
+In the future we will try to release tar-1.14 as soon as possible and
+start merging with paxutils afterwards. We'll also try to rewrite
+some parts of the documentation after paxutils has been merged.