I got the following error on SVN rev 1627, wxGTK 2.6.2, Slackware 10.2, and it seems related to wxSmith:
g++ -DHAVE_CONFIG_H -I. -I. -I../../../../../src/sdk -I/usr/lib/wx/include/gtk2-unicode-release-2.6 -I/usr/include/wx-2.6 -DGTK_NO_CHECK_CASTS -D__WXGTK__ -D_FILE_OFFSET_BITS=64 -D_LARGE_FILES -D_LARGEFILE_SOURCE=1 -I../../../../../src/sdk -I../../../../../src/sdk/wxscintilla/include -I../../../../../src/sdk/propgrid/include -I/usr/lib/wx/include/gtk2-unicode-release-2.6 -I/usr/include/wx-2.6 -DGTK_NO_CHECK_CASTS -D__WXGTK__ -D_FILE_OFFSET_BITS=64 -D_LARGE_FILES -D_LARGEFILE_SOURCE=1 -g -O2 -O2 -ffast-math -I/usr/lib/wx/include/gtk2-unicode-release-2.6 -I/usr/include/wx-2.6 -DGTK_NO_CHECK_CASTS -D__WXGTK__ -D_FILE_OFFSET_BITS=64 -D_LARGE_FILES -D_LARGEFILE_SOURCE=1 -MT wxsstdmanager.lo -MD -MP -MF .deps/wxsstdmanager.Tpo -c wxsstdmanager.cpp -fPIC -DPIC -o .libs/wxsstdmanager.o
In file included from ../properties/wxsstringlistcheckproperty.h:4,
from wxschecklistbox.h:5,
from wxsstdmanager.cpp:40:
../../../../../src/sdk/propgrid/include/wx/propgrid/propdev.h:18:3: #error "propdev.h must be included *before* advprops.h"
make[6]: *** [wxsstdmanager.lo] Error 1
make[6]: Leaving directory `/home/ruslan/codeblocks-build/trunk/src/plugins/contrib/wxSmith/defwidgets'
make[5]: *** [all-recursive] Error 1
make[5]: Leaving directory `/home/ruslan/codeblocks-build/trunk/src/plugins/contrib/wxSmith'
make[4]: *** [all] Error 2
make[4]: Leaving directory `/home/ruslan/codeblocks-build/trunk/src/plugins/contrib/wxSmith'
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory `/home/ruslan/codeblocks-build/trunk/src/plugins/contrib'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/home/ruslan/codeblocks-build/trunk/src/plugins'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/home/ruslan/codeblocks-build/trunk/src'
make: *** [all-recursive] Error 1