Add comment to CheckVectorCast.h

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@44356 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/Sema/Sema.h b/Sema/Sema.h
index 21a7cdcbfc8e5b457b0600fecde6816b9ccbf0ff..1b232df356b748ab8ff604653def5ed0359fb0f4 100644 (file)
--- a/Sema/Sema.h
+++ b/Sema/Sema.h
@@ -696,6 +696,9 @@ private:
                              QualType ElementType, bool isStatic, 
                              int &nInitializers, bool &hadError);
                              
+  // CheckVectorCast - check type constraints for vectors. 
+  // Since vectors are an extension, there are no C standard reference for this.
+  // We allow casting between vectors and integer datatypes of the same size.
   // returns true if the cast is invalid
   bool CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty);