Hi,
I try to extract a source code syntax tree for c code from the
c-frontend of the gcc.
Therefore i have written a plugin which registers a callback for
PLUGIN_PRE_GENERICIZE.
My problem is that the c-frontend directly breaks while-, do- and
for-loops in statement list and
does not use FOR_STMT nodes like the c++-frontend.
To reconstruct this statement lists to a tree structure like the one in
the c++ frontend i have added
a few markings in struct tree_base. The gool is to have a node for the
init, the condition, the increment
and the body of the loop as children of the FOR_STMT node. But this
reconstruction should only take
place in a seperate tree in my plugin not the c-frontend internal tree.
That works so far but not for empty do-loops with an always false condition:
do {
} while(0);
In this case in c-typeck.c:c_finish_loop() nothing is added to the
frontend internal tree.
My question is: Is it possible to add a NOP_EXPR, which has no further
children, to the current
statement list. If yes how?
I could then set a few of my flags in tree_base for this NOP_EXPR and
would be able to trac empty
do-loops.
If this is possible, am i right in the assumption that this NOP_EXPR is
removed from the internal tree
in later optimization steps but not before my PLUGIN_PRE_GENERICIZE
callback was executed?
Thanks for your help and attention,
Markus
