I found a small issue in SVN version of Qwt.
qwt_point_mapper.cpp contains:
Qt Code:
  1. #include <qwt_point_mapper.h>
  2. #include <qwt_scale_map.h>
  3. #include <qwt_pixel_matrix.h>
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I think these should be in "", not <>. Otherwise it may break in some other build systems (like the one I use) which don't set the include path to Qwt directory when building it.