Attaching comments to declarations: parse the comment in context of the

declaration it was attached to.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@162033 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 51 insertions, 4 deletions

diff --git a/include/clang/AST/ASTContext.h b/include/clang/AST/ASTContext.h
index 7b44d10f64..cad3ad2b5f 100644
--- a/include/clang/AST/ASTContext.h
+++ b/include/clang/AST/ASTContext.h
@@ -474,8 +474,17 @@ public:
       Data.setPointer(RC);
     }
 
+    const Decl *getOriginalDecl() const LLVM_READONLY {
+      return OriginalDecl;
+    }
+
+    void setOriginalDecl(const Decl *Orig) {
+      OriginalDecl = Orig;
+    }
+
   private:
     llvm::PointerIntPair<const RawComment *, 2, Kind> Data;
+    const Decl *OriginalDecl;
   };
 
   /// \brief Mapping from declarations to comments attached to any
@@ -504,7 +513,12 @@ public:
 
   /// \brief Return the documentation comment attached to a given declaration.
   /// Returns NULL if no comment is attached.
-  const RawComment *getRawCommentForAnyRedecl(const Decl *D) const;
+  ///
+  /// \param OriginalDecl if not NULL, is set to declaration AST node that had
+  /// the comment, if the comment we found comes from a redeclaration.
+  const RawComment *getRawCommentForAnyRedecl(
+                                      const Decl *D,
+                                      const Decl **OriginalDecl = NULL) const;
 
   /// Return parsed documentation comment attached to a given declaration.
   /// Returns NULL if no comment is attached.
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index d12effcd3c..c02132329e 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -209,7 +209,9 @@ const Decl *adjustDeclToTemplate(const Decl *D) {
 }
 } // unnamed namespace
 
-const RawComment *ASTContext::getRawCommentForAnyRedecl(const Decl *D) const {
+const RawComment *ASTContext::getRawCommentForAnyRedecl(
+                                                const Decl *D,
+                                                const Decl **OriginalDecl) const {
   D = adjustDeclToTemplate(D);
 
   // Check whether we have cached a comment for this declaration already.
@@ -218,13 +220,17 @@ const RawComment *ASTContext::getRawCommentForAnyRedecl(const Decl *D) const {
         RedeclComments.find(D);
     if (Pos != RedeclComments.end()) {
       const RawCommentAndCacheFlags &Raw = Pos->second;
-      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl)
+      if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
+        if (OriginalDecl)
+          *OriginalDecl = Raw.getOriginalDecl();
         return Raw.getRaw();
+      }
     }
   }
 
   // Search for comments attached to declarations in the redeclaration chain.
   const RawComment *RC = NULL;
+  const Decl *OriginalDeclForRC = NULL;
   for (Decl::redecl_iterator I = D->redecls_begin(),
                              E = D->redecls_end();
        I != E; ++I) {
@@ -234,16 +240,19 @@ const RawComment *ASTContext::getRawCommentForAnyRedecl(const Decl *D) const {
       const RawCommentAndCacheFlags &Raw = Pos->second;
       if (Raw.getKind() != RawCommentAndCacheFlags::NoCommentInDecl) {
         RC = Raw.getRaw();
+        OriginalDeclForRC = Raw.getOriginalDecl();
         break;
       }
     } else {
       RC = getRawCommentForDeclNoCache(*I);
+      OriginalDeclForRC = *I;
       RawCommentAndCacheFlags Raw;
       if (RC) {
         Raw.setRaw(RC);
         Raw.setKind(RawCommentAndCacheFlags::FromDecl);
       } else
         Raw.setKind(RawCommentAndCacheFlags::NoCommentInDecl);
+      Raw.setOriginalDecl(*I);
       RedeclComments[*I] = Raw;
       if (RC)
         break;
@@ -253,10 +262,14 @@ const RawComment *ASTContext::getRawCommentForAnyRedecl(const Decl *D) const {
   // If we found a comment, it should be a documentation comment.
   assert(!RC || RC->isDocumentation());
 
+  if (OriginalDecl)
+    *OriginalDecl = OriginalDeclForRC;
+
   // Update cache for every declaration in the redeclaration chain.
   RawCommentAndCacheFlags Raw;
   Raw.setRaw(RC);
   Raw.setKind(RawCommentAndCacheFlags::FromRedecl);
+  Raw.setOriginalDecl(OriginalDeclForRC);
 
   for (Decl::redecl_iterator I = D->redecls_begin(),
                              E = D->redecls_end();
@@ -277,10 +290,14 @@ comments::FullComment *ASTContext::getCommentForDecl(const Decl *D) const {
   if (Pos != ParsedComments.end())
     return Pos->second;
 
-  const RawComment *RC = getRawCommentForAnyRedecl(D);
+  const Decl *OriginalDecl;
+  const RawComment *RC = getRawCommentForAnyRedecl(D, &OriginalDecl);
   if (!RC)
     return NULL;
 
+  if (D != OriginalDecl)
+    return getCommentForDecl(OriginalDecl);
+
   comments::FullComment *FC = RC->parse(*this, D);
   ParsedComments[Canonical] = FC;
   return FC;
diff --git a/test/Sema/warn-documentation.cpp b/test/Sema/warn-documentation.cpp
index a361d57baa..d99520b673 100644
--- a/test/Sema/warn-documentation.cpp
+++ b/test/Sema/warn-documentation.cpp
@@ -641,6 +641,22 @@ void test_attach37<int>::test_attach38(int aaa, int bbb) {}
 template<typename T>
 void test_attach37<T>::test_attach39(int aaa, int bbb) {}
 
+// We used to emit warning that parameter 'a' is not found because we parsed
+// the comment in context of the redeclaration which does not have parameter
+// names.
+template <typename T>
+struct test_attach38 {
+  /*!
+    \param a  First param
+    \param b  Second param
+  */
+  template <typename B>
+  void test_attach39(T a, B b);
+};
+
+template <>
+template <typename B>
+void test_attach38<int>::test_attach39(int, B);
 
 
 // PR13411, reduced.  We used to crash on this.