Touchup CheckSingleAssignmentConstraints() and CheckCompareOperands() to check for block pointers.

Added a couple FIXME's wrt PointLikeType. If the author reads this, it would be great to get some background on this class (thanks in advance).


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@55778 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 25 insertions, 1 deletions

diff --git a/include/clang/AST/Type.h b/include/clang/AST/Type.h
index b3fefb265e..3eb28a86c0 100644
--- a/include/clang/AST/Type.h
+++ b/include/clang/AST/Type.h
@@ -530,6 +530,9 @@ protected:
 };
 
 /// PointerLikeType - Common base class for pointers and references.
+/// FIXME: Add more documentation on this classes design point. For example,
+/// should BlockPointerType inherit from it? Is the concept of a PointerLikeType
+/// in the C++ standard?
 ///
 class PointerLikeType : public Type {
   QualType PointeeType;
@@ -577,6 +580,9 @@ protected:
 /// BlockPointerType - pointer to a block type.
 /// This type is to represent types syntactically represented as
 /// "void (^)(int)", etc. Pointee is required to always be a function type.
+/// FIXME: Should BlockPointerType inherit from PointerLikeType? It could
+/// simplfy some type checking code, however PointerLikeType doesn't appear
+/// to be used by the type checker.
 ///
 class BlockPointerType : public Type, public llvm::FoldingSetNode {
   QualType PointeeType;  // Block is some kind of pointer type
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 37172cbf0d..02169e6db8 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -1578,7 +1578,8 @@ Sema::AssignConvertType
 Sema::CheckSingleAssignmentConstraints(QualType lhsType, Expr *&rExpr) {
   // C99 6.5.16.1p1: the left operand is a pointer and the right is
   // a null pointer constant.
-  if ((lhsType->isPointerType() || lhsType->isObjCQualifiedIdType()) 
+  if ((lhsType->isPointerType() || lhsType->isObjCQualifiedIdType() ||
+       lhsType->isBlockPointerType()) 
       && rExpr->isNullPointerConstant(Context)) {
     ImpCastExprToType(rExpr, lhsType);
     return Compatible;
@@ -1944,6 +1945,23 @@ QualType Sema::CheckCompareOperands(Expr *&lex, Expr *&rex, SourceLocation loc,
     ImpCastExprToType(lex, rType); // promote the integer to pointer
     return Context.IntTy;
   }
+  // Handle block pointers.
+  if (lType->isBlockPointerType() && rType->isIntegerType()) {
+    if (!RHSIsNull)
+      Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
+           lType.getAsString(), rType.getAsString(),
+           lex->getSourceRange(), rex->getSourceRange());
+    ImpCastExprToType(rex, lType); // promote the integer to pointer
+    return Context.IntTy;
+  }
+  if (lType->isIntegerType() && rType->isBlockPointerType()) {
+    if (!LHSIsNull)
+      Diag(loc, diag::ext_typecheck_comparison_of_pointer_integer,
+           lType.getAsString(), rType.getAsString(),
+           lex->getSourceRange(), rex->getSourceRange());
+    ImpCastExprToType(lex, rType); // promote the integer to pointer
+    return Context.IntTy;
+  }
   return InvalidOperands(loc, lex, rex);
 }