[OpenCL] Diagnose variadic arguments

OpenCL disallows using variadic arguments (s6.9.e and s6.12.5 OpenCL v2.0)
apart from some exceptions:
- printf
- enqueue_kernel

This change adds error diagnostic for variadic functions but accepts printf
and any compiler internal function (which should cover __enqueue_kernel_XXX cases).

It also unifies diagnostic with block prototype and adds missing uncaught cases for blocks.

llvm-svn: 285395

3 files changed, 20 insertions, 16 deletions

diff --git a/clang/lib/Headers/opencl-c.h b/clang/lib/Headers/opencl-c.h
index f8e132040d6..3eb6dc712f3 100644
--- a/clang/lib/Headers/opencl-c.h
+++ b/clang/lib/Headers/opencl-c.h
@@ -15459,9 +15459,11 @@ half16 __ovld __cnfn shuffle2(half8 x, half8 y, ushort16 mask);
 half16 __ovld __cnfn shuffle2(half16 x, half16 y, ushort16 mask);
 #endif //cl_khr_fp16
 
+#if __OPENCL_C_VERSION__ >= CL_VERSION_1_2
 // OpenCL v1.2 s6.12.13, v2.0 s6.13.13 - printf
 
 int printf(__constant const char* st, ...);
+#endif
 
 // OpenCL v1.1 s6.11.3, v1.2 s6.12.14, v2.0 s6.13.14 - Image Read and Write Functions
 
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index a94ed532944..f91e9dcdd6d 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -6888,17 +6888,6 @@ void Sema::CheckVariableDeclarationType(VarDecl *NewVD) {
         NewVD->setInvalidDecl();
         return;
       }
-      // OpenCL v2.0 s6.12.5 - Blocks with variadic arguments are not supported.
-      // TODO: this check is not enough as it doesn't diagnose the typedef
-      const BlockPointerType *BlkTy = T->getAs<BlockPointerType>();
-      const FunctionProtoType *FTy =
-          BlkTy->getPointeeType()->getAs<FunctionProtoType>();
-      if (FTy && FTy->isVariadic()) {
-        Diag(NewVD->getLocation(), diag::err_opencl_block_proto_variadic)
-            << T << NewVD->getSourceRange();
-        NewVD->setInvalidDecl();
-        return;
-      }
     }
     // OpenCL v1.2 s6.5 - All program scope variables must be declared in the
     // __constant address space.
diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
index 2d612e5a0f9..4e6725eb626 100644
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -4043,13 +4043,26 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
         }
       }
 
+      if (LangOpts.OpenCL) {
         // OpenCL v2.0 s6.12.5 - A block cannot be the return value of a
         // function.
-      if (LangOpts.OpenCL && (T->isBlockPointerType() || T->isImageType() ||
-                              T->isSamplerT() || T->isPipeType())) {
-        S.Diag(D.getIdentifierLoc(), diag::err_opencl_invalid_return)
-            << T << 1 /*hint off*/;
-        D.setInvalidType(true);
+        if (T->isBlockPointerType() || T->isImageType() || T->isSamplerT() ||
+            T->isPipeType()) {
+          S.Diag(D.getIdentifierLoc(), diag::err_opencl_invalid_return)
+              << T << 1 /*hint off*/;
+          D.setInvalidType(true);
+        }
+        // OpenCL doesn't support variadic functions and blocks
+        // (s6.9.e and s6.12.5 OpenCL v2.0) except for printf.
+        // We also allow here any toolchain reserved identifiers.
+        if (FTI.isVariadic &&
+            !(D.getIdentifier() &&
+              ((D.getIdentifier()->getName() == "printf" &&
+                LangOpts.OpenCLVersion >= 120) ||
+               D.getIdentifier()->getName().startswith("__")))) {
+          S.Diag(D.getIdentifierLoc(), diag::err_opencl_variadic_function);
+          D.setInvalidType(true);
+        }
       }
 
       // Methods cannot return interface types. All ObjC objects are