<html>
  <head>
    <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
  </head>
  <body bgcolor="#FFFFFF" text="#000000">
    <div class="moz-cite-prefix">On 18/04/16 20:32, Richard Smith wrote:<br>
    </div>
    <blockquote
cite="mid:CAOfiQq=QDO5TBmpDkiFTBKPp4_JywFFJFzA0F9fEaPL71tEy6g@mail.gmail.com"
      type="cite">
      <div dir="ltr">
        <div class="gmail_extra">
          <div class="gmail_quote">On Mon, Apr 18, 2016 at 6:28 AM,
            Vassil Vassilev <span dir="ltr"><<a
                moz-do-not-send="true"
                href="mailto:v.g.vassilev@gmail.com" target="_blank"><a class="moz-txt-link-abbreviated" href="mailto:v.g.vassilev@gmail.com">v.g.vassilev@gmail.com</a></a>></span>
            wrote:<br>
            <blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><span
                class="">On 08/04/16 03:24, Richard Smith via
                cfe-commits wrote:<br>
                <blockquote class="gmail_quote" style="margin:0px 0px
                  0px
0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">Author:
                  rsmith<br>
                  Date: Thu Apr  7 20:23:59 2016<br>
                  New Revision: 265766<br>
                  <br>
                  URL: <a moz-do-not-send="true"
                    href="http://llvm.org/viewvc/llvm-project?rev=265766&view=rev"
                    rel="noreferrer" target="_blank">http://llvm.org/viewvc/llvm-project?rev=265766&view=rev</a><br>
                  Log:<br>
                  [modules] Add a comment to explain why -E leaves some
                  #includes in the preprocessed output.<br>
                  <br>
                  Modified:<br>
                     
                   cfe/trunk/lib/Frontend/PrintPreprocessedOutput.cpp<br>
                       cfe/trunk/test/Modules/preprocess.cpp<br>
                  <br>
                  Modified:
                  cfe/trunk/lib/Frontend/PrintPreprocessedOutput.cpp<br>
                  URL: <a moz-do-not-send="true"
href="http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Frontend/PrintPreprocessedOutput.cpp?rev=265766&r1=265765&r2=265766&view=diff"
                    rel="noreferrer" target="_blank">http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Frontend/PrintPreprocessedOutput.cpp?rev=265766&r1=265765&r2=265766&view=diff</a><br>
==============================================================================<br>
                  --- cfe/trunk/lib/Frontend/PrintPreprocessedOutput.cpp
                  (original)<br>
                  +++ cfe/trunk/lib/Frontend/PrintPreprocessedOutput.cpp
                  Thu Apr  7 20:23:59 2016<br>
                  @@ -336,7 +336,9 @@ void
                  PrintPPOutputPPCallbacks::Inclusion<br>
                          OS << "#include "<br>
                             << (IsAngled ? '<' : '"')<br>
                             << FileName<br>
                  -         << (IsAngled ? '>' : '"');<br>
                  +         << (IsAngled ? '>' : '"')<br>
                  +         << " /* clang -E: implicit import for
                  module "<br>
                  +         << Imported->getFullModuleName()
                  << " */";<br>
                </blockquote>
              </span>
              It seems that in some cases the FileName needs to be
              tweaked to be able to compile the output back. For
              instance:<br>
              clang -I folder/ file.cxx<br>
              cat file.cxx<br>
              #include "subfolder/A.h"<br>
              <br>
              cat folder/subfolder/A.h<br>
              #include "B.h"<br>
              <br>
              B.h resides in folder/subfolder/ and FileName argument
              would be B.h causing the printer to generate #include
              "B.h" /* clang -E: implicit import for... */ which cannot
              be compiled back.</blockquote>
            <div><br>
            </div>
            <div>Ugh, yeah, that makes sense.</div>
            <div><br>
            </div>
            <div>It seems superficially that what we should do for a
              file found relative to the current file (or in MSVC mode,
              for a file found relative to a possibly-indirect includer
              of the current file) is to prepend the path from that
              file's search path to the current file. That is, if we
              find "foo/bar.h" in search path "includes/x", and we find
              "baz/quux.h" relative to bar.h, we should produce the path
              "foo/baz/quux.h" (to be found relative to "includes/x").
              However, that won't work if there is a prior include path
              that also contains a "foo/baz/quux.h", so we would need to
              also include the search path in the include path. And
              *that* won't work if . is not a search path and one of the
              search paths is a relative path.</div>
          </div>
        </div>
      </div>
    </blockquote>
    :( at first looked like an easy, nice solution, but apparently "twin
    peaks" killer phase is true again :)<br>
    <blockquote
cite="mid:CAOfiQq=QDO5TBmpDkiFTBKPp4_JywFFJFzA0F9fEaPL71tEy6g@mail.gmail.com"
      type="cite">
      <div dir="ltr">
        <div class="gmail_extra">
          <div class="gmail_quote">
            <div><br>
            </div>
            <div>I wonder whether the problem is really that we're
              handling #include search paths incorrectly in the presence
              of #line markers.</div>
          </div>
        </div>
      </div>
    </blockquote>
    I am not sure I understand this. Could you give an example?<br>
    <blockquote
cite="mid:CAOfiQq=QDO5TBmpDkiFTBKPp4_JywFFJFzA0F9fEaPL71tEy6g@mail.gmail.com"
      type="cite">
      <div dir="ltr">
        <div class="gmail_extra">
          <div class="gmail_quote">
            <div> Perhaps for the relative path search we should somehow
              instruct clang to look for files relative to the presumed
              file rather than the physical file?</div>
          </div>
        </div>
      </div>
    </blockquote>
    Could we detect that we are compiling a preprocessed file? I guess
    there are traces, eg. include stack push/pop values...<br>
    <blockquote
cite="mid:CAOfiQq=QDO5TBmpDkiFTBKPp4_JywFFJFzA0F9fEaPL71tEy6g@mail.gmail.com"
      type="cite">
      <div dir="ltr">
        <div class="gmail_extra">
          <div class="gmail_quote">
            <div> That would match our intent for these files. However,
              this doesn't match the GCC behavior, so we probably can't
              do it by default. =/</div>
          </div>
        </div>
      </div>
    </blockquote>
    <br>
    <blockquote
cite="mid:CAOfiQq=QDO5TBmpDkiFTBKPp4_JywFFJFzA0F9fEaPL71tEy6g@mail.gmail.com"
      type="cite">
      <div dir="ltr">
        <div class="gmail_extra">
          <div class="gmail_quote">
            <div> </div>
            <blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">
              <div class="">
                <div class="h5">
                  <blockquote class="gmail_quote" style="margin:0px 0px
                    0px
0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"> 
                        }<br>
                          // Since we want a newline after the @import,
                    but not a #<line>, start a new<br>
                          // line immediately.<br>
                    <br>
                    Modified: cfe/trunk/test/Modules/preprocess.cpp<br>
                    URL: <a moz-do-not-send="true"
href="http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/preprocess.cpp?rev=265766&r1=265765&r2=265766&view=diff"
                      rel="noreferrer" target="_blank">http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/preprocess.cpp?rev=265766&r1=265765&r2=265766&view=diff</a><br>
==============================================================================<br>
                    --- cfe/trunk/test/Modules/preprocess.cpp (original)<br>
                    +++ cfe/trunk/test/Modules/preprocess.cpp Thu Apr  7
                    20:23:59 2016<br>
                    @@ -1,6 +1,6 @@<br>
                      // RUN: rm -rf %t<br>
                      // RUN: %clang_cc1 -fmodules
                    -fimplicit-module-maps -fmodules-cache-path=%t -I
                    %S/Inputs -x c++ -E %s | \<br>
                    -// RUN:   FileCheck -strict-whitespace %s
                    --check-prefix=CHECK --check-prefix=CXX<br>
                    +// RUN:   FileCheck -strict-whitespace %s
                    --check-prefix=CHECK --check-prefix=CXX
                    --check-prefix=CXX-DASHE<br>
                      // RUN: %clang_cc1 -fmodules
                    -fimplicit-module-maps -fmodules-cache-path=%t -I
                    %S/Inputs -x objective-c -E %s | \<br>
                      // RUN:   FileCheck -strict-whitespace %s
                    --check-prefix=CHECK --check-prefix=OBJC<br>
                      // RUN: %clang_cc1 -fmodules
                    -fimplicit-module-maps -fmodules-cache-path=%t -I
                    %S/Inputs -x c++ -E -frewrite-includes %s | \<br>
                    @@ -14,7 +14,9 @@ foo bar baz<br>
                      // The weird {{ }} here is to prevent the
                    -frewrite-includes test from matching its own CHECK
                    lines.<br>
                        // CXX: #include{{ }}"dummy.h"<br>
                    +// CXX-DASHE-SAME: /* clang -E: implicit import for
                    module dummy */<br>
                      // CXX: #include{{ }}"dummy.h"<br>
                    +// CXX-DASHE-SAME: /* clang -E: implicit import for
                    module dummy */<br>
                      // CXX: foo bar baz<br>
                        // OBJC: @import{{ }}dummy; /* clang<br>
                    <br>
                    <br>
                    _______________________________________________<br>
                    cfe-commits mailing list<br>
                    <a moz-do-not-send="true"
                      href="mailto:cfe-commits@lists.llvm.org"
                      target="_blank">cfe-commits@lists.llvm.org</a><br>
                    <a moz-do-not-send="true"
                      href="http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits"
                      rel="noreferrer" target="_blank">http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits</a><br>
                  </blockquote>
                  <br>
                </div>
              </div>
            </blockquote>
          </div>
          <br>
        </div>
      </div>
    </blockquote>
    <br>
  </body>
</html>