From 70ff1091315c60fed68d7197c637ec8c588e67a1 Mon Sep 17 00:00:00 2001
From: Dmitri Gribenko <gribozavr@gmail.com>
Date: Fri, 24 Aug 2012 00:05:30 +0000
Subject: [PATCH] Comment semantic analysis: treat function typedefs as
 functions so that one can use \param and \returns in documentation.

Fixes PR13533.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@162507 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/clang/AST/Comment.h      |  4 ++-
 lib/AST/Comment.cpp              | 53 +++++++++++++++++++++++++++++++-
 test/Sema/warn-documentation.cpp | 23 ++++++++++++++
 test/Sema/warn-documentation.m   |  8 ++++-
 4 files changed, 85 insertions(+), 3 deletions(-)

diff --git a/include/clang/AST/Comment.h b/include/clang/AST/Comment.h
index 01aaac3f77..09d0a26731 100644
--- a/include/clang/AST/Comment.h
+++ b/include/clang/AST/Comment.h
@@ -942,7 +942,9 @@ struct DeclInfo {
     /// \li member function,
     /// \li member function template,
     /// \li member function template specialization,
-    /// \li ObjC method.
+    /// \li ObjC method,
+    /// \li a typedef for a function pointer, member function pointer,
+    ///     ObjC block.
     FunctionKind,
 
     /// Something that we consider a "class":
diff --git a/lib/AST/Comment.cpp b/lib/AST/Comment.cpp
index 8a711f0c1f..2af3896156 100644
--- a/lib/AST/Comment.cpp
+++ b/lib/AST/Comment.cpp
@@ -240,7 +240,58 @@ void DeclInfo::fill() {
   case Decl::Namespace:
     Kind = NamespaceKind;
     break;
-  case Decl::Typedef:
+  case Decl::Typedef: {
+    Kind = TypedefKind;
+    // If this is a typedef to something we consider a function, extract
+    // arguments and return type.
+    const TypedefDecl *TD = cast<TypedefDecl>(ThisDecl);
+    const TypeSourceInfo *TSI = TD->getTypeSourceInfo();
+    if (!TSI)
+      break;
+    TypeLoc TL = TSI->getTypeLoc().getUnqualifiedLoc();
+    while (true) {
+      TL = TL.IgnoreParens();
+      // Look through typedefs.
+      if (TypedefTypeLoc *TypedefTL = dyn_cast<TypedefTypeLoc>(&TL)) {
+        TSI = TypedefTL->getTypedefNameDecl()->getTypeSourceInfo();
+        if (TSI)
+          break;
+        TL = TSI->getTypeLoc().getUnqualifiedLoc();
+        continue;
+      }
+      // Look through qualified types.
+      if (QualifiedTypeLoc *QualifiedTL = dyn_cast<QualifiedTypeLoc>(&TL)) {
+        TL = QualifiedTL->getUnqualifiedLoc();
+        continue;
+      }
+      // Look through pointer types.
+      if (PointerTypeLoc *PointerTL = dyn_cast<PointerTypeLoc>(&TL)) {
+        TL = PointerTL->getPointeeLoc().getUnqualifiedLoc();
+        continue;
+      }
+      if (BlockPointerTypeLoc *BlockPointerTL =
+              dyn_cast<BlockPointerTypeLoc>(&TL)) {
+        TL = BlockPointerTL->getPointeeLoc().getUnqualifiedLoc();
+        continue;
+      }
+      if (MemberPointerTypeLoc *MemberPointerTL =
+              dyn_cast<MemberPointerTypeLoc>(&TL)) {
+        TL = MemberPointerTL->getPointeeLoc().getUnqualifiedLoc();
+        continue;
+      }
+      // Is this a typedef for a function type?
+      if (FunctionTypeLoc *FTL = dyn_cast<FunctionTypeLoc>(&TL)) {
+        Kind = FunctionKind;
+        ArrayRef<ParmVarDecl *> Params = FTL->getParams();
+        ParamVars = ArrayRef<const ParmVarDecl *>(Params.data(),
+                                                  Params.size());
+        ResultType = FTL->getResultLoc().getType();
+        break;
+      }
+      break;
+    }
+    break;
+  }
   case Decl::TypeAlias:
     Kind = TypedefKind;
     break;
diff --git a/test/Sema/warn-documentation.cpp b/test/Sema/warn-documentation.cpp
index 1cd1358521..43143ff83d 100644
--- a/test/Sema/warn-documentation.cpp
+++ b/test/Sema/warn-documentation.cpp
@@ -250,6 +250,29 @@ int test_param17(int a);
 /// \param x2 Ccc.
 int test_param18(int x1, int x2, int x3);
 
+// expected-warning@+2 {{parameter 'bbb' not found in the function declaration}} expected-note@+2 {{did you mean 'aaa'?}}
+/// \param aaa Meow.
+/// \param bbb Bbb.
+/// \returns aaa.
+typedef int test_param19(int aaa);
+
+// expected-warning@+2 {{parameter 'bbb' not found in the function declaration}} expected-note@+2 {{did you mean 'aaa'?}}
+/// \param aaa Meow.
+/// \param bbb Bbb.
+/// \returns aaa.
+typedef int (*test_param20)(int aaa);
+
+// expected-warning@+2 {{parameter 'bbb' not found in the function declaration}} expected-note@+2 {{did you mean 'aaa'?}}
+/// \param aaa Meow.
+/// \param bbb Bbb.
+/// \returns aaa.
+typedef int (* const test_param21)(int aaa);
+
+// expected-warning@+2 {{parameter 'bbb' not found in the function declaration}} expected-note@+2 {{did you mean 'aaa'?}}
+/// \param aaa Meow.
+/// \param bbb Bbb.
+/// \returns aaa.
+typedef int (C::*test_param22)(int aaa);
 
 // expected-warning@+1 {{'\tparam' command used in a comment that is not attached to a template declaration}}
 /// \tparam T Aaa
diff --git a/test/Sema/warn-documentation.m b/test/Sema/warn-documentation.m
index d6af6edcc8..04ae4ab648 100644
--- a/test/Sema/warn-documentation.m
+++ b/test/Sema/warn-documentation.m
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fsyntax-only -Wno-objc-root-class -Wdocumentation -Wdocumentation-pedantic -verify %s
+// RUN: %clang_cc1 -fsyntax-only -fblocks -Wno-objc-root-class -Wdocumentation -Wdocumentation-pedantic -verify %s
 
 @class NSString;
 
@@ -91,3 +91,9 @@ int b;
 - (void)test2:(NSString *)aaa;
 @end
 
+// expected-warning@+2 {{parameter 'bbb' not found in the function declaration}} expected-note@+2 {{did you mean 'aaa'?}}
+/// \param aaa Meow.
+/// \param bbb Bbb.
+/// \returns aaa.
+typedef int (^test_param1)(int aaa);
+
-- 
2.40.0