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    <div class="moz-cite-prefix">Good point. Do you have in mind calling
      'clang::Sema::MergeVarDeclTypes' or we to just "duplicate" the
      logic in clang::ASTDeclReader::mergeRedeclarable?<br>
      On 05/02/16 02:50, Richard Smith via cfe-commits wrote:<br>
    </div>
    <blockquote
cite="mid:CAOfiQqmS-Fi82Na7aK360aO_Li7Rie8E83RKYjWAMtpj7UYvtw@mail.gmail.com"
      type="cite">
      <div dir="ltr">I suspect we'll need to do a little more than this:
        when we rebuild the redeclaration chain, we should probably
        propagate the complete type to later redeclarations in the same
        scope. Otherwise, if we import a module that has a complete type
        and one that has an incomplete type, the declaration found by
        name lookup might be the one with the incomplete type, possibly
        resulting in rejects-valid on code like this:
        <div><br>
        </div>
        <div>a.h:</div>
        <div>extern int a[5];</div>
        <div><br>
        </div>
        <div>b.h:</div>
        <div>extern int a[];</div>
        <div><br>
        </div>
        <div>x.cc:</div>
        <div>#include "a.h"</div>
        <div>#include "b.h"</div>
        <div>int k = sizeof(a);</div>
        <div>
          <div class="gmail_extra"><br>
            <div class="gmail_quote">On Fri, Jan 22, 2016 at 11:03 AM,
              Yaron Keren via cfe-commits <span dir="ltr"><<a
                  moz-do-not-send="true"
                  href="mailto:cfe-commits@lists.llvm.org"
                  target="_blank"><a class="moz-txt-link-abbreviated" href="mailto:cfe-commits@lists.llvm.org">cfe-commits@lists.llvm.org</a></a>></span>
              wrote:<br>
              <blockquote class="gmail_quote" style="margin:0 0 0
                .8ex;border-left:1px #ccc solid;padding-left:1ex">Author:
                yrnkrn<br>
                Date: Fri Jan 22 13:03:27 2016<br>
                New Revision: 258524<br>
                <br>
                URL: <a moz-do-not-send="true"
                  href="http://llvm.org/viewvc/llvm-project?rev=258524&view=rev"
                  rel="noreferrer" target="_blank">http://llvm.org/viewvc/llvm-project?rev=258524&view=rev</a><br>
                Log:<br>
                Merge templated static member variables, fixes <a
                  moz-do-not-send="true" href="http://llvm.org/pr26179"
                  rel="noreferrer" target="_blank"><a class="moz-txt-link-freetext" href="http://llvm.org/pr26179">http://llvm.org/pr26179</a></a>.<br>
                <br>
                Patch by Vassil Vassilev!<br>
                Reviewed by Richard Smith.<br>
                <br>
                <br>
                Added:<br>
                    cfe/trunk/test/Modules/Inputs/PR26179/<br>
                    cfe/trunk/test/Modules/Inputs/PR26179/A.h<br>
                    cfe/trunk/test/Modules/Inputs/PR26179/B.h<br>
                    cfe/trunk/test/Modules/Inputs/PR26179/basic_string.h<br>
                   
                cfe/trunk/test/Modules/Inputs/PR26179/module.modulemap<br>
                    cfe/trunk/test/Modules/pr26179.cpp<br>
                Modified:<br>
                    cfe/trunk/lib/Serialization/ASTReaderDecl.cpp<br>
                <br>
                Modified: cfe/trunk/lib/Serialization/ASTReaderDecl.cpp<br>
                URL: <a moz-do-not-send="true"
href="http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Serialization/ASTReaderDecl.cpp?rev=258524&r1=258523&r2=258524&view=diff"
                  rel="noreferrer" target="_blank">http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Serialization/ASTReaderDecl.cpp?rev=258524&r1=258523&r2=258524&view=diff</a><br>
==============================================================================<br>
                --- cfe/trunk/lib/Serialization/ASTReaderDecl.cpp
                (original)<br>
                +++ cfe/trunk/lib/Serialization/ASTReaderDecl.cpp Fri
                Jan 22 13:03:27 2016<br>
                @@ -2595,8 +2595,24 @@ static bool
                isSameEntity(NamedDecl *X, N<br>
                   // Variables with the same type and linkage match.<br>
                   if (VarDecl *VarX = dyn_cast<VarDecl>(X)) {<br>
                     VarDecl *VarY = cast<VarDecl>(Y);<br>
                -    return (VarX->getLinkageInternal() ==
                VarY->getLinkageInternal()) &&<br>
                -     
                VarX->getASTContext().hasSameType(VarX->getType(),
                VarY->getType());<br>
                +    if (VarX->getLinkageInternal() ==
                VarY->getLinkageInternal()) {<br>
                +      ASTContext &C = VarX->getASTContext();<br>
                +      if (C.hasSameType(VarX->getType(),
                VarY->getType()))<br>
                +        return true;<br>
                +<br>
                +      // We can get decls with different types on the
                redecl chain. Eg.<br>
                +      // template <typename T> struct S { static
                T Var[]; }; // #1<br>
                +      // template <typename T> T
                S<T>::Var[sizeof(T)]; // #2<br>
                +      // Only? happens when completing an incomplete
                array type. In this case<br>
                +      // when comparing #1 and #2 we should go through
                their elements types.<br>
                +      const ArrayType *VarXTy =
                C.getAsArrayType(VarX->getType());<br>
                +      const ArrayType *VarYTy =
                C.getAsArrayType(VarY->getType());<br>
                +      if (!VarXTy || !VarYTy)<br>
                +        return false;<br>
                +      if (VarXTy->isIncompleteArrayType() ||
                VarYTy->isIncompleteArrayType())<br>
                +        return
                C.hasSameType(VarXTy->getElementType(),
                VarYTy->getElementType());<br>
                +    }<br>
                +    return false;<br>
                   }<br>
                <br>
                   // Namespaces with the same name and inlinedness
                match.<br>
                <br>
                Added: cfe/trunk/test/Modules/Inputs/PR26179/A.h<br>
                URL: <a moz-do-not-send="true"
href="http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/Inputs/PR26179/A.h?rev=258524&view=auto"
                  rel="noreferrer" target="_blank">http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/Inputs/PR26179/A.h?rev=258524&view=auto</a><br>
==============================================================================<br>
                --- cfe/trunk/test/Modules/Inputs/PR26179/A.h (added)<br>
                +++ cfe/trunk/test/Modules/Inputs/PR26179/A.h Fri Jan 22
                13:03:27 2016<br>
                @@ -0,0 +1,4 @@<br>
                +#include "basic_string.h"<br>
                +#include "B.h"<br>
                +<br>
                +int *p = a;<br>
                <br>
                Added: cfe/trunk/test/Modules/Inputs/PR26179/B.h<br>
                URL: <a moz-do-not-send="true"
href="http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/Inputs/PR26179/B.h?rev=258524&view=auto"
                  rel="noreferrer" target="_blank">http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/Inputs/PR26179/B.h?rev=258524&view=auto</a><br>
==============================================================================<br>
                --- cfe/trunk/test/Modules/Inputs/PR26179/B.h (added)<br>
                +++ cfe/trunk/test/Modules/Inputs/PR26179/B.h Fri Jan 22
                13:03:27 2016<br>
                @@ -0,0 +1,2 @@<br>
                +#include "basic_string.h"<br>
                +extern int a[5];<br>
                <br>
                Added:
                cfe/trunk/test/Modules/Inputs/PR26179/basic_string.h<br>
                URL: <a moz-do-not-send="true"
href="http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/Inputs/PR26179/basic_string.h?rev=258524&view=auto"
                  rel="noreferrer" target="_blank">http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/Inputs/PR26179/basic_string.h?rev=258524&view=auto</a><br>
==============================================================================<br>
                --- cfe/trunk/test/Modules/Inputs/PR26179/basic_string.h
                (added)<br>
                +++ cfe/trunk/test/Modules/Inputs/PR26179/basic_string.h
                Fri Jan 22 13:03:27 2016<br>
                @@ -0,0 +1,14 @@<br>
                +#ifndef _GLIBCXX_STRING<br>
                +#define _GLIBCXX_STRING 1<br>
                +<br>
                +template<typename T><br>
                +struct basic_string {<br>
                +  static T _S_empty_rep_storage[];<br>
                +};<br>
                +<br>
                +template<typename T><br>
                +T
                basic_string<T>::_S_empty_rep_storage[sizeof(T)];<br>
                +<br>
                +extern int a[];<br>
                +<br>
                +#endif<br>
                <br>
                Added:
                cfe/trunk/test/Modules/Inputs/PR26179/module.modulemap<br>
                URL: <a moz-do-not-send="true"
href="http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/Inputs/PR26179/module.modulemap?rev=258524&view=auto"
                  rel="noreferrer" target="_blank">http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/Inputs/PR26179/module.modulemap?rev=258524&view=auto</a><br>
==============================================================================<br>
                ---
                cfe/trunk/test/Modules/Inputs/PR26179/module.modulemap
                (added)<br>
                +++
                cfe/trunk/test/Modules/Inputs/PR26179/module.modulemap
                Fri Jan 22 13:03:27 2016<br>
                @@ -0,0 +1,9 @@<br>
                +module A {<br>
                +  header "A.h"<br>
                +  export *<br>
                +}<br>
                +<br>
                +module B {<br>
                +  header "B.h"<br>
                +  export *<br>
                +}<br>
                <br>
                Added: cfe/trunk/test/Modules/pr26179.cpp<br>
                URL: <a moz-do-not-send="true"
href="http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/pr26179.cpp?rev=258524&view=auto"
                  rel="noreferrer" target="_blank">http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Modules/pr26179.cpp?rev=258524&view=auto</a><br>
==============================================================================<br>
                --- cfe/trunk/test/Modules/pr26179.cpp (added)<br>
                +++ cfe/trunk/test/Modules/pr26179.cpp Fri Jan 22
                13:03:27 2016<br>
                @@ -0,0 +1,7 @@<br>
                +// RUN: rm -rf %t<br>
                +// RUN: %clang_cc1 -I%S/Inputs/PR26179 -verify %s<br>
                +// RUN: %clang_cc1 -fmodules
                -fmodule-map-file=%S/Inputs/PR26179/module.modulemap
                -fmodules-cache-path=%t -I%S/Inputs/PR26179 -verify %s<br>
                +<br>
                +#include "A.h"<br>
                +<br>
                +// expected-no-diagnostics<br>
                <br>
                <br>
                _______________________________________________<br>
                cfe-commits mailing list<br>
                <a moz-do-not-send="true"
                  href="mailto:cfe-commits@lists.llvm.org">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>
            </div>
            <br>
          </div>
        </div>
      </div>
      <br>
      <fieldset class="mimeAttachmentHeader"></fieldset>
      <br>
      <pre wrap="">_______________________________________________
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</pre>
    </blockquote>
    <br>
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