On Fri, Jan 14, 2011 at 4:59 PM, Daniel Bünzli <daniel.buenzli@erratique.ch> wrote:

> So it appears that printing an exception changes the backtrace. Is that
> possible?

I don't know about the details of backtrace recording but I suspect
that the call to the printing function interferes with the previously
recorded backtrace.

What works for me is to immediately get the backtrace as a string [1]
with Printexc.get_backtrace (), then print the exception and then
print the string.

Also bear in mind that sometimes native backtrace are not as precise
as those in bytecode (tail calls and optimizations ?).

Daniel

[1]
Btw. the api could really have given us a list of strings (or even of
string * string * int * (int * int)). I already had to parse that
string to properly format backtraces.