Douglas Bollinger <[EMAIL PROTECTED]> posted [EMAIL PROTECTED], excerpted below, on Mon, 21 Aug 2006 18:01:18 -0400:
> Does having my entire system (and espcially the gtk libs) compiled with > -fomit-frame-pointer pretty much render my system useless for debugging? I don't claim to be a "coding guru" or debugger of any significant skill, but here goes, as I understand it. =8^) How -fomit-frame-pointer affects debugging is arch dependent. For amd64 (my arch), I've been told -fomit-frame-pointer does not cause debugging issues (in 64-bit code). As a result, it's a default optimization enabled by even first-level optimizations (-O, see the gcc manpage). For x86 (and therefore for 32-bit x86 compatible code on amd64), omitting the frame-pointer DOES affect debugging, but ONLY on the libraries and executables where the flag is used. (As a result it's not enabled by any -O level and must be invoked directly, again, gcc manpage.) Assuming you are on x86, then, compiling pan without -fomit-frame-pointer should enable you to debug pan's own functions. As soon as you hit the gtk or other libraries (glibc certainly, gcc's libstdc++ also since pan is now C++, other dependencies) compiled with -fomit-frame-pointer, however, you'll be in black-box territory -- you won't be able to trace into them. Whether that kills debugging then depends on whether you can get enough info from what /is/ frame-pointered to be useful troubleshooting your particular problem, or not. FWIW, the glibc and gcc/libstdc++ debugging may well not be worth it, given the necessary time to remerge. gtk+-2.* and related dependencies (pango, glib, atk) don't take so much time to remerge, however, so you might consider them, at least gtk. Also note that depending on the issue, strace may be able to give you the info you need. It works differently, by tracing system calls and the like, so is still useful with -fomit-frame-pointer, giving you stuff like file and socket activity, etc. I'll often use strace for such admin-type tasks as figuring out exactly where an app is looking for it's config file, for instance, altho often the output is overwhelming on its own (those who've never run it often have no idea how many files an app may stat and open if they exist at launch -- often hundreds -- one gains a vastly greater appreciation for the benefits of in-memory disk cache!) and must be grepped to reduce it to a human-admin manageable size. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman _______________________________________________ Pan-users mailing list Pan-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/pan-users
