On Fri, Oct 19, 2012 at 2:01 PM, Daniel Dunbar <[email protected]> wrote: > On Fri, Oct 19, 2012 at 1:08 PM, Michael Spencer <[email protected]> > wrote: >> On Fri, Oct 19, 2012 at 12:48 PM, Daniel Dunbar <[email protected]> wrote: >>> On Fri, Oct 19, 2012 at 12:39 PM, Michael Spencer <[email protected]> >>> wrote: >>>> On Fri, Oct 19, 2012 at 10:38 AM, Daniel Dunbar <[email protected]> wrote: >>>>> Hi Michael, >>>>> >>>>> I understand what this patch does, but I don't really understand the >>>>> motivation for it, yet. >>>>> >>>>> Why is this the "main feature" needed for sane gnu-ld and link command >>>>> line support? >>>>> >>>>> It seems to me, that what you really need for those is a completely >>>>> separate option parsing table. I can see how this patch could be >>>>> useful if you wanted to accept the same options for the link.exe >>>>> parsing just with a '/' at the front, but that doesn't seem right to >>>>> me. It seems to me that the link.exe parsing or cl.exe parsing would >>>>> end up using a completely separate parsing table. >>>>> >>>>> Can you explain? >>>>> >>>>> - Daniel >>>> >>>> The option tables would be completely separate. This is needed because >>>> link supports both / and - prefixes for all options. gnu-ld supports - >>>> and -- for almost all options. >>> >>> If the option tables are separate, can't we dramatically simplify this >>> patch by making this a feature of the option table then? So that an >>> option table can opt in to explicitly specifying all prefixes, and >>> then we don't need to clutter up the Clang/GCC option table. Option >>> tables which didn't opt-in to that would be required to supply a list >>> of possible prefixes. >>> >>> - Daniel >> >> This would work if clang and gcc used only one prefix. There are 36 >> options that use both - and --, and 103 that use --. > > I think you misunderstood me, I was proposing initializing the option > table with a special mode that says "all prefixes are defined as part > of the option". Only the Clang/GCC table would use that. > > - Daniel
Ah, I see. I feel this would greatly complicate the code as it would require either two different parsing paths in OptParser, or normalizing in the tablegen emitter. - Michael Spencer >> I can simplify this patch by defaulting to - via tblgen and only >> changing those 139 options that are special. >> >> - Michael Spencer >> >>>> From the ld man page: >>>> >>>> "For options whose names are multiple letters, either one dash or two >>>> can precede the option name; for example, -trace-symbol and >>>> --trace-symbol are equivalent. Note---there is one exception to this >>>> rule. Multiple letter options that start with a lower case 'o' can >>>> only be preceded by two dashes. This is to reduce confusion with the >>>> -o option. So for example -omagic sets the output file name to magic >>>> whereas --omagic sets the NMAGIC flag on the output." >>>> >>>> - Michael Spencer >>>> >>>>> >>>>> On Thu, Oct 18, 2012 at 3:53 PM, Michael Spencer <[email protected]> >>>>> wrote: >>>>>> Hi ddunbar, >>>>>> >>>>>> This patch adds support for multiple prefixes per option. This is the >>>>>> main feature needed for sane gnu-ld and link command line support. >>>>>> >>>>>> Most of the ["-"]'s can be refactored to a common class in tablegen, but >>>>>> I have a few more widespread tablegen changes I want to make before >>>>>> doing all the refactoring needed. >>>>>> >>>>>> http://llvm-reviews.chandlerc.com/D69 >>>>>> >>>>>> Files: >>>>>> include/clang/Driver/Arg.h >>>>>> include/clang/Driver/CC1AsOptions.h >>>>>> include/clang/Driver/CC1AsOptions.td >>>>>> include/clang/Driver/CC1Options.td >>>>>> include/clang/Driver/OptParser.td >>>>>> include/clang/Driver/OptTable.h >>>>>> include/clang/Driver/Option.h >>>>>> include/clang/Driver/Options.h >>>>>> include/clang/Driver/Options.td >>>>>> lib/Driver/Arg.cpp >>>>>> lib/Driver/ArgList.cpp >>>>>> lib/Driver/CC1AsOptions.cpp >>>>>> lib/Driver/Driver.cpp >>>>>> lib/Driver/DriverOptions.cpp >>>>>> lib/Driver/OptTable.cpp >>>>>> lib/Driver/Option.cpp >>>>>> lib/Driver/Tools.cpp >>>>>> lib/Frontend/CompilerInvocation.cpp >>>>>> utils/TableGen/OptParserEmitter.cpp _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
