that fixes the warning. For the record, it was:
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Compiling linking_2d_and_3d ...
make[1]: Entering directory `/home/lrineau/CGAL/releases-and-testsuites/CGAL-3.4-I-407/test_i686_Linux-2.6_g++-4.3.1_CentOS-5.1-O3/Triangulation_3_Examples'
/usr/local/gcc43/bin/g++ -I../../include -Wall -frounding-math '-I/home/lrineau/CGAL/releases-and-testsuites/CGAL-3.4-I-407/include/CGAL/config/i686_Linux-2.6_g++-4.3.1_CentOS-5.1-O3' '-I/home/lrineau/CGAL/releases-and-testsuites/CGAL-3.4-I-407/include' -O3 -pipe -I/home/lrineau/CGAL/bimap -I/usr/lib/qt-3.3/include -DCGAL_USE_F2C -DCGAL_USE_F2C -c linking_2d_and_3d.cpp
../../include/CGAL/Compact_container.h: In member function 'typename CGAL::Triangulation_data_structure_2<Vb, Fb>::Vertex_handle CGAL::Triangulation_data_structure_2<Vb, Fb>::insert_dim_up(typename CGAL::Compact_container<typename Vb::Rebind_TDS<CGAL::Triangulation_data_structure_2<Vb, Fb> >::Other, CGAL::Default_argument>::iterator, bool) [with Vb = My_vertex_2<CGAL::Dummy_tds_3, CGAL::Triangulation_ds_vertex_base_2<void> >, Fb = CGAL::Triangulation_ds_face_base_2<void>]':
../../include/CGAL/Compact_container.h:772: warning: array subscript is above array bounds
/usr/local/gcc43/bin/g++ -o linking_2d_and_3d linking_2d_and_3d.o '-L/home/lrineau/CGAL/releases-and-testsuites/CGAL-3.4-I-407/lib/i686_Linux-2.6_g++-4.3.1_CentOS-5.1-O3' -L/usr/lib/qt-3.3/lib -Wl,-R/home/lrineau/CGAL/releases-and-testsuites/CGAL-3.4-I-407/lib/i686_Linux-2.6_g++-4.3.1_CentOS-5.1-O3:/usr/lib/qt-3.3/lib -lCGAL -lCGALcore++ -lCGALQt -lCGALimageIO -lCGALPDB -lqt-mt -llapack -lGL -lGLU -lblas -lz -lmpfr -lgmpxx -lgmp -lX11 -lboost_thread -lboost_program_options -lm
make[1]: Leaving directory `/home/lrineau/CGAL/releases-and-testsuites/CGAL-3.4-I-407/test_i686_Linux-2.6_g++-4.3.1_CentOS-5.1-O3/Triangulation_3_Examples'
Executing linking_2d_and_3d ...
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Maybe a gcc bug. Howerver, with that patch, the code seems easier to read
(the variable that contains the dimension is now named "dim", instead of
"i", and is filled as soon as the dimension() of the triangulation is
updated).
This adds requirements to TriangulationTraits2 concept :
Less_x_2 and Less_y_2 predicates.
Also fixes a few bugs in RT2 (hidden points were sometimes forgotten
in degenerate dimensions.)