Looking at the code of Curl_resolv_timeout() in hostip.c, I think
that in case of a timeout, the signal handler for SIGALRM never
gets removed. I think that in my case it gets executed at some
point later on when execution has long left Curl_resolv_timeout()
or even the cURL library.

The code that is jumped to with siglongjmp() simply sets the
error message to "name lookup timed out" and then returns with
CURLRESOLV_ERROR. I guess that instead of simply returning
without cleaning up, the code should have a goto that jumps to
the spot right after the call to Curl_resolv().

which could have caused a double free when reusing curl handle.

Error codes were not properly returned to the main curl code (and on to apps
using libcurl).

tftp was crapping out when tsize == 0 on upload, but I see no reason to fail
to upload just because the remote file is zero-length.  Ignore tsize option on
upload.

another shot at the ftp_init() icc 9.1 optimizer issue

replaced intel compiler option -no-ansi-alias with -fno-strict-aliasing

update outdated serial number

  The problem mentioned on Dec 10 2009
  (http://curl.haxx.se/bug/view.cgi?id=2905220) was only partially fixed.
  Partially because an easy handle can be associated with many connections in
  the cache (e.g. if there is a redirect during the lifetime of the easy
  handle).  The previous patch only cleaned up the first one. The new fix now
  removes the easy handle from all connections, not just the first one.

fix compiler warning

watt32 compilation fix

  the easy interface was used.

expressions

Added another VS10 version string

fix line break

removed usage of 's6_addr', fixing compilation issue triggered with no
longer using 'in6_addr' but only our 'ares_in6_addr' struct

Added IPv6 name servers support

Constantine Sapuntzakis detected and fixed a double free in builds done
with threaded resolver enabled (Windows default configuration) that would
get triggered when a curl handle is closed while doing DNS resolution.

Added SIZEOF_INT and SIZEOF_SHORT definitions for VMS configuration file

CURLOPT_HEADERFUNCTION and CURLOPT_WRITEFUNCTION more consistent

  ran into some issues with the GSSAPI tests in configure.ac. The tests first
  try to determine the include dirs and libs and set CPPFLAGS and LIBS
  accordingly. It then checks for the headers and finally sets LIBS a second
  time, causing the libs to be included twice. The first setting of LIBS seems
  redundant and should be left out, since the first part is otherwise just
  about finding headers.

  My second issue is that 'krb5-config --libs gssapi' on Darwin is less than
  useless and returns junk that, while it happens to work with gcc, causes
  clang to choke. For example, --libs returns $CFLAGS along with the libs,
  which is really retarded. Simply setting 'LIBS="$LIBS -lgssapi_krb5
  -lresolv"' on Darwin is sufficient.

  makes sure that when using sub-second timeouts, there's no final bad 1000ms
  wait. Previously, a sub-second timeout would often make the elapsed time end
  up the time rounded up to the nearest second (e.g. 1s for 200ms timeout)