On Mon, Sep 17, 2012 at 3:04 PM, Argyrios Kyrtzidis <[email protected]> wrote: > > On Sep 17, 2012, at 2:38 PM, James Dennett <[email protected]> wrote: > >> On Mon, Sep 17, 2012 at 2:22 PM, Argyrios Kyrtzidis <[email protected]> >> wrote: >>> On Sep 17, 2012, at 12:44 PM, James Dennett <[email protected]> wrote: >>> >>>> On Mon, Sep 10, 2012 at 7:17 PM, Argyrios Kyrtzidis <[email protected]> >>>> wrote: >>>>> Author: akirtzidis >>>>> Date: Mon Sep 10 21:17:21 2012 >>>>> New Revision: 163588 >>>>> >>>>> URL: http://llvm.org/viewvc/llvm-project?rev=163588&view=rev >>>>> Log: >>>>> [libclang] Fix getting a cursor inside an angled #include directive. >>>>> >>>>> Fixed by pointing the end location of the preprocessed entity for the >>>>> #include >>>>> at the closing '>', instead of the start of '<'. >>>>> >>>>> rdar://11113134 >>>>> >>>>> Modified: >>>>> cfe/trunk/lib/Lex/PPDirectives.cpp >>>>> cfe/trunk/test/Index/c-index-getCursor-pp.c >>>>> >>>>> Modified: cfe/trunk/lib/Lex/PPDirectives.cpp >>>>> URL: >>>>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Lex/PPDirectives.cpp?rev=163588&r1=163587&r2=163588&view=diff >>>>> ============================================================================== >>>>> --- cfe/trunk/lib/Lex/PPDirectives.cpp (original) >>>>> +++ cfe/trunk/lib/Lex/PPDirectives.cpp Mon Sep 10 21:17:21 2012 >>>>> @@ -1296,6 +1296,9 @@ >>>>> case tok::string_literal: >>>>> Filename = getSpelling(FilenameTok, FilenameBuffer); >>>>> End = FilenameTok.getLocation(); >>>>> + // For an angled include, point the end location at the closing '>'. >>>>> + if (FilenameTok.is(tok::angle_string_literal)) >>>>> + End = End.getLocWithOffset(Filename.size()-1); >>>>> CharEnd = End.getLocWithOffset(Filename.size()); >>>>> break; >>>>> >>>>> >>>>> Modified: cfe/trunk/test/Index/c-index-getCursor-pp.c >>>>> URL: >>>>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Index/c-index-getCursor-pp.c?rev=163588&r1=163587&r2=163588&view=diff >>>>> ============================================================================== >>>>> --- cfe/trunk/test/Index/c-index-getCursor-pp.c (original) >>>>> +++ cfe/trunk/test/Index/c-index-getCursor-pp.c Mon Sep 10 21:17:21 2012 >>>>> @@ -15,6 +15,8 @@ >>>>> >>>>> const char *fname = __FILE__; >>>>> >>>>> +#include <a.h> >>>>> + >>>>> // RUN: c-index-test -cursor-at=%s:1:11 -I%S/Inputs %s | FileCheck >>>>> -check-prefix=CHECK-1 %s >>>>> // CHECK-1: macro definition=OBSCURE >>>>> // RUN: c-index-test -cursor-at=%s:2:14 -I%S/Inputs %s | FileCheck >>>>> -check-prefix=CHECK-2 %s >>>>> @@ -31,6 +33,8 @@ >>>>> // CHECK-7: macro expansion=B:12:9 >>>>> // RUN: c-index-test -cursor-at=%s:16:25 -I%S/Inputs %s | FileCheck >>>>> -check-prefix=CHECK-8 %s >>>>> // CHECK-8: macro expansion=__FILE__ >>>>> +// RUN: c-index-test -cursor-at=%s:18:12 -I%S/Inputs %s | FileCheck >>>>> -check-prefix=CHECK-9 %s >>>>> +// CHECK-9: inclusion directive=a.h >>>>> >>>>> // Same tests, but with "editing" optimizations >>>>> // RUN: env CINDEXTEST_EDITING=1 c-index-test -cursor-at=%s:1:11 >>>>> -I%S/Inputs %s | FileCheck -check-prefix=CHECK-1 %s >>>> >>>> This change broke clients that implement >>>> PPCallbacks::InclusionDirective, which now receive the location of the >>>> closing '>' rather than the location of the token that they're >>>> expecting based on the spec: >>>> /// \param EndLoc The location of the last token within the >>>> inclusion >>>> /// directive. >>>> The last (preprocessing) token is the whole of <filename>, of type >>>> tok::angle_string_literal. >>>> >>>> Could we consider reverting this change and finding an alternative way >>>> to fix libclang without breaking/changing the lower-level interface? >>> >>> Hi James, >>> >>> This is not a high-level libclang issue. >> >> Apologies, I was going by the change description "[libclang] Fix >> getting a cursor inside an angled #include directive.", and that the >> only tests I saw included were for libclang. (That does suggests that >> we're missing tests for this in the appropriate place.) > > You're right, a preprocessing record unit test is also needed. > >> >>> The preprocessing record needs to know the '>' location and depends on the >>> PPCallbacks::InclusionDirective callback. Previously this callback did not >>> provide a way to reliably get at that location. >> >> I'm not sure about that -- it provided a way to get there, but it was >> necessary to skip over the filename. > > If the include filename was formed via a macro expansion then you had an > EndLoc pointing at '>'. So this was the situation: > > No macro expansions involved: EndLoc points at '<' > With macro expansion: EndLoc points at '>'. > > The receiver had no easy way to know which case it was. With the change it > always pointed at '>'.
Checking which character is at the EndLoc isn't so hard, but I take your point. >> With your change a similar trick >> is required for code wanting to get to the filename, but only for >> #include <filename>, not for #include "filename". (Why are the two >> cases different? Currently the callback returns the location of the >> opening quote for the #include "name" case, and the closing one for >> #include <name>. The asymmetry seems strange.) > > There's an asymmetry due to how lexing would behave if you pointed at the > beginning of the filename, for example: > > #include "filename" > If you point at the opening quote and start lexing you will get the > tok::string_literal token, the same that the preprocessor saw. Then you can > get at the character range of the whole filename input by checking the token > size. > > #include <filename> > if you point at the opening '<' and start lexing you will get a tok::less > token, you need to get into the special "parsing include directive" mode to > receive a tok::angle_string_literal token. > So just pointing at '<' will not allow you to easily lex and get the > character range of the filename input. I was assuming that you'd lex correctly, which means being in the right mode to lex an include directive in this case. I don't think it matters that if you lex incorrectly that you'll get the wrong results. >>> I believe we still need to modify the bahavior of the InclusionDirective >>> callback and focus the discussion there. >>> >>> How about reverting the EndLoc adjustment but have the InclusionDirective >>> also pass the FilenameTok token so that receivers of the callback can have >>> more information for the inclusion directive (then the preprocessing record >>> can do the adjustment itself). >> >> That sounds good to me -- though I'm not sure if we need to pass >> EndLoc if we pass the FilenameTok (possibly for cases where the >> filename comes from macro expansion? I'm not all that familiar with >> this code). > > Yes, the EndLoc is necessary because if there are macro expansions involved > then the FilenameTok token will be a tok::less for '<'. This is going to be "fun" to document thoroughly enough for clients to be written based on the spec alone -- but then the quirky lexing rules for this context are what they are, and Clang can't (and shouldn't) completely hide them. -- James _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
