Hello! Thank you for the information. I am also quite confused with this issue. I note that it seems that given the following statement:
m_pstSwtmrCBArray.27_1 = m_pstSwtmrCBArray; where m_pstSwtmrCBArray is a global variable (a pointer). When passing a tree pointer `v` referring to m_pstSwtmrCBArray to the following statement: auto temp = TREE_CODE(v); It will cause a segmentation fault of my GIMPLE pass. Not sure what's actually going on here... Best, Shuai On Fri, Feb 19, 2021 at 4:54 PM Prathamesh Kulkarni < prathamesh.kulka...@linaro.org> wrote: > On Fri, 19 Feb 2021 at 10:31, Shuai Wang via Gcc <gcc@gcc.gnu.org> wrote: > > > > Hello, > > > > I noticed that tree_node is implemented as a union ( > > https://code.woboq.org/gcc/gcc/tree-core.h.html#tree_node). However, I > > cannot find a way of checking whether the current tree_node is really a > > base or type. > > > > For instance, currently when I am using: > > > > is_gimple_constant(v) > > > > Given `v` as a tree type but NOT base type, the above statement would > > crash. I am thinking there should be a method like: > > > > is_tree_base(v) == false > > > > or something like this; however, I couldn't find one. Can anyone shed > some > > lights on this? Thank you very much! > If you want to ascertain which class the tree node belongs to, you can > use either TREE_CODE, or one of the _P macros > defined in tree.h. If you use an accessor that needs tree node > belonging to a certain class, then you need to check for it before > hand. > For example before using DECL_NAME on a tree node, you need to > explicitly check if it's indeed a decl_node using DECL_P. > For is_gimple_constant(v), it will return true if v is a one of the > constant nodes (*_CST), and false otherwise, so I don't see how it > will crash if you > pass a non-constant node ? > > Thanks, > Prathamesh > > > > best, > > Shuai >
