Hi guys, (DJ especially, since you might be in a position to know something about this).
I came across a book on Google books, which suggested that functions containing "setjmp" might not end up being optimised by the compiler. http://books.google.co.uk/books?id=Pq7pHwG1_OkC&pg=PA174&lpg=PA174&dq=setjmp+branch+optimization&source=web&ots=4W5ZMoh1lM&sig=4U05kWsQEAIHuux1EMSoKtHNN1s&hl=en&sa=X&oi=book_result&resnum=1&ct=result "In practice, this is usually handled by not attempting to optimise routines that include a call to setjmp(), but putting in phantom control-flow edges is a (usually very pessimistic) alternative." PCB uses setjmp quite a lot to short-circuit a deep call-graph of searches and callbacks, when it finds something it is interested in, both in the connectivity scanning, polygon and rtree code. Are we likely to be hurting the chance of optimisation by doing this, or is it the lesser of two evils? Is the book reference outdated, or not relevant to GCC 4.x? Best regards, -- Peter Clifton Electrical Engineering Division, Engineering Department, University of Cambridge, 9, JJ Thomson Avenue, Cambridge CB3 0FA Tel: +44 (0)7729 980173 - (No signal in the lab!) _______________________________________________ geda-dev mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-dev
