doc/README.windows

Note for Windows users:

  It is highly recommended to declare the Windows OS version you are
targetting when building the library as well as when using it. You can do so
thanks to the well known Microsoft macros WINVER, _WIN32_WINDOWS or
_WIN32_WINNT, see your platform SDK documentation for a description
of those macros and how to use them. To define it when building the
library, use the configure script --extra-cxxflag option. Here is the
configuration to build STLport using Visual Studio 2005 and targetting
Windows XP:

configure -c msvc8 --extra-cxxflag "/D_WIN32_WINNT=0x0501"

  If you do not declare it at build time STLport will adapt to the PSDK in
use, windows.h gives a default value to WINVER. However, when using the
library, windows.h is not necessarily included, at least not by STLport
internally, so none of the macros are defined which will result in an
inconsistency in the build process which most of time will generate undefined
behavior at runtime.

  Here is the main reason for following this advise, the Windows 95
compatibility issue:

  Because of a modification in the behavior of the Win32 API functions
InterlockedIncrement and InterlockedDecrement after Windows 95, STLport
libraries built for Windows 95 cannot be used to generate an application
built for Windows XP for instance. So, if you build STLport with a Windows
95 PSDK, STLport will be ready for Windows 95. If you then use it without
defining _WIN32_WINDOWS to signal Windows 95 compatibility, STLport will
consider that it can use latest Windows OS features like the new
InterlockedIncrement and InterlockedDecrement functions which change the
memory footprint of some internal STLport objects making it incompatible
with the libraries built for Windows 95.

  Normally, doing so wouldn't generate any compilation or link error, you
would only experiment undefined behavior at runtime. In order to make this
problem more obvious STLport forces a link time error in debug mode (_DEBUG
macro defined).

Unresolved symbol will be:
  - 'building_for_at_least_windows98_but_library_built_for_windows95'
  if you are trying to use STLport libraries built for Windows 98 or later
  to generate an application targetting the Windows 95 platform.
  - 'building_for_windows95_but_library_built_for_at_least_windows98'
  if you are trying to use STLport libraries built for Windows 95 to generate
  an appliation targetting the
  
  Windows XP platform for instance.

  Of course, targetting the latest Windows OS versions will give you the best
performance from STLport. This is why when none of the platform macros are
defined STLport consider that there is no minimum OS requirement and will
use the latest API functions. There is only one exception to this behavior,
the SwitchToThread function that is used only if you define _WIN32_WINNT to a
value higher or equal to 0X0400.