> -----Original Message----- > From: Dwarf-Discuss [mailto:[email protected]] On > Behalf Of Jan Kratochvil > Sent: Tuesday, June 13, 2017 2:23 PM > To: [email protected] > Subject: [Dwarf-Discuss] .debug_names: Preallocation of DW_IDX_* for > static/extern symbols > > Hello, > > filed: > http://dwarfstd.org/ShowIssue.php?issue=170527.1 > > When a debugger wants to print 'somename' it logically tries to find first > 'somename' as an external symbol in all available libraries. Only if none > such external symbol is found the debugger starts searching for a static > 'somename' symbol in those libraries. > > This requires to know whether a symbol in .debug_names index has > DW_AT_external or not. Otherwise a lot of needless CU expansions happen. > This extension improves performance gain of the .debug_names index. > > Discovered in an original fix by Doug Evans - GDB Bug 14125: > https://sourceware.org/bugzilla/show_bug.cgi?id=14125 > > Proposing and asking for pre-allocation: > DW_IDX_static = 6 = DW_FORM_flag_present = DIE's DW_AT_external is not > present > DW_IDX_external = 7 = DW_FORM_flag_present = DIE's DW_AT_external is > present > > Is it OK to start using these numbers to be in DWARF-6 or should stay in > the > DW_IDX_lo_user..DW_IDX_hi_user range?
There's no guarantee that your proposal would be accepted unmodified. You should use the lo_user..hi_user range for anything you do now. --paulr > > > Thanks, > Jan Kratochvil > _______________________________________________ > Dwarf-Discuss mailing list > [email protected] > http://lists.dwarfstd.org/listinfo.cgi/dwarf-discuss-dwarfstd.org _______________________________________________ Dwarf-Discuss mailing list [email protected] http://lists.dwarfstd.org/listinfo.cgi/dwarf-discuss-dwarfstd.org
