I tested the latest snapshot of the library with Mingw.
There is no localtime_r function present in Mingw so datetime.cpp 
does not compile. I commented out the line to check the remainder of
the build and it was otherwise fine: 0 warnings, 0 errors.
I think there's a straightforward fix; according to the following
sources, localtime on MinGW is thread-safe so we should be able to shift
calls to localtime_r onto localtime:
"Mingw uses the runtime libraries distributed with the OS."
Specifically, in the readme file for mingw-runtime-3.11 source:
"Mingw32 programs use CRTDLL.DLL to provide their C run time library
functions, and CRTDLL.DLL is supplied with all current Win32 platforms."
"Both the 32-bit and 64-bit versions of gmtime, mktime, mkgmtime, and
localtime all use a single tm structure per thread for the conversion.
Each call to one of these routines destroys the result of the previous
By this I read that Mingw is simply delegating localtime straight into
the standard library shipped on all versions of Windows, meaning that
for Mingw, we can do the same as in pthreads:
#define localtime_r( _clock, _result ) \
( *(_result) = *localtime( (_clock) ), \
This can be surrounded by #if defined __MINGW32_VERSION and #endif in an
appropriate place in platform.h. Perhaps it would be better to modify
datetime.cpp as localtime_r is not used anywhere else within mysqlpp and
some users may have their own workarounds for the localtime_r issue
elsewhere in their header files.
And maybe a slightly different macro (or even an inline function) would
be more suitable as the pthreads macro above leads to a warning (at
least with -Wall anyway): right-hand operand of comma has no effect.
Or use boost's date and time library.