hi, While trying to debug the intialization and shutdown of my code, I stumbled upon cxa_atexit and cxa_finalize: I tried to grep a bit the gcc and glibc codebases to understand who calls them and with which arguments but I am a bit lost so, help would be welcome. I can see how each bit and piece of the puzzle works but the global picture somewhat escapes me. 1) I can't figure out who inserts the calls to __cxa_finalize/atexit. I suspect that it's gcc but I can't see which piece of gcc code does this. I thought that it would be the gcc/crtstuff.c file but it includes only a call to __cxa_finalize from the .fini section and only when CRTSTUFF_O is defined and this does not appear to be defined on my platform. (fedora11 x86_64). So, who makes sure that these functions are called during .init/.fini ? 2) I can't figure out how the code comes up with the third argument to __cxa_atexit and the first argument to __cxa_finalize. I expected some kind of per-binary global variable (say, __dsa_handle) for __cxa_finalize which would be set by the code calling __cxa_atexit but I can't see this symbol defined anywhere in my binaries. Of course, I can't see how __cxa_atexit comes up with this third argument. Is the __dso_handle really expected to be a the void *handle associated by the dynamic linker to this binary or is it merely expected to be a unique address specific to this binary ? 3) why is this scheme used instead of just using atexit+the normal constructor/destructor things on a per-binary basis ? Mathieu -- Mathieu Lacage <mathieu.lacage@xxxxxxxxx>
