Add comment explaining that autoconf's failure to find getaddrinfo()

on Windows is now a feature, not a bug.

configure

@@ -14550,8 +14550,11 @@ done
-# system's version of getaddrinfo(), if any, may be used only if we found
-# a definition for struct addrinfo; see notes in src/include/getaddrinfo.h
+# System's version of getaddrinfo(), if any, may be used only if we found
+# a definition for struct addrinfo; see notes in src/include/getaddrinfo.h.
+# (Note: the AC_REPLACE_FUNCS probe fails on Windows, where the available
+# versions of getaddrinfo don't follow normal C call protocol.  This is OK
+# because we want to use our own getaddrinfo.c on Windows anyway.)
 if test x"$ac_cv_type_struct_addrinfo" = xyes ; then
 for ac_func in getaddrinfo

configure.in

 dnl Process this file with autoconf to produce a configure script.
-dnl $PostgreSQL: pgsql/configure.in,v 1.424 2005/08/24 21:32:37 pgsql Exp $
+dnl $PostgreSQL: pgsql/configure.in,v 1.425 2005/08/25 02:28:03 tgl Exp $
 dnl
 dnl Developers, please strive to achieve this order:
 dnl
@@ -883,8 +883,11 @@ fi
 
 AC_REPLACE_FUNCS([crypt fseeko getopt getrusage inet_aton random rint srandom strdup strerror strtol strtoul unsetenv])
 
-# system's version of getaddrinfo(), if any, may be used only if we found
-# a definition for struct addrinfo; see notes in src/include/getaddrinfo.h
+# System's version of getaddrinfo(), if any, may be used only if we found
+# a definition for struct addrinfo; see notes in src/include/getaddrinfo.h.
+# (Note: the AC_REPLACE_FUNCS probe fails on Windows, where the available
+# versions of getaddrinfo don't follow normal C call protocol.  This is OK
+# because we want to use our own getaddrinfo.c on Windows anyway.)
 if test x"$ac_cv_type_struct_addrinfo" = xyes ; then
   AC_REPLACE_FUNCS([getaddrinfo])
 else