dspoon@fenix.Atlanta.NCR.COM (David B. Witherspoon) (09/24/88)
I attempted to respond to Greg Bollella through the mail, but it got bounced. I'm posting the response here instead. In article <4275@thorin.cs.unc.edu> you write: > >I have heard about an option '+e' used in the C++ compilation >with CFront that is supposed to somehow allow the optimization >of the virtual function table. I cannot find it documented >anywhere. Could someone shed some light? > >Thanks > >Greg Bollella Since I'm not using C++ on UNIX, I don't know first-hand. But I trust the info I got: Without the "+e" option, every time you #include a ".h" file containing a class definition in a ".c++" file, a new copy the v-table is created. Like so: y.h ----- a.c #include's y.h ---> v-tab b.c #include's y.h ---> v-tab [etc] Using the "+e" option results in just ONE v-table being created (and extern'ed appropriately) like so: y.h ----- a.c #include's y.h -\ b.c #include's y.h ---> v-tab c.c #include's y.h -/ Hope that helps. I like pictures...as you can tell. [I can't claim this as my own...credit to Bruce Frederiksen at NCR,] [SE-Retail, in Dayton, OH. ] -------------------------------David Witherspoon------------------------------- D.Witherspoon@Atlanta.NCR.COM | "It's all just 1's and 0's you know!" NCR Sys Engineering-Retail/Atlanta | MY OPINIONS...ALL MINE!!! | - me