From: Sven van Haastregt <sven.vanhaastregt@arm.com>
Date: Wed, 26 Jun 2019 13:31:24 +0000 (+0000)
Subject: [OpenCL] Improve diagnostic for placement new
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=f269c05476a4fcb055be233e013966ad0b25391f;p=clang

[OpenCL] Improve diagnostic for placement new

Without an explicit declaration for placement new, clang would reject
uses of placement new with "'default new' is not supported in OpenCL
C++".  This may mislead users into thinking that placement new is not
supported, see e.g. PR42060.

Clarify that placement new requires an explicit declaration.

Differential Revision: https://reviews.llvm.org/D63561

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@364423 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 2abf7d73c1..b9d081c7e2 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -8809,6 +8809,9 @@ def ext_opencl_ext_vector_type_rgba_selector: ExtWarn<
   "vector component name '%0' is an OpenCL version 2.2 feature">,
   InGroup<OpenCLUnsupportedRGBA>;
 
+def err_openclcxx_placement_new : Error<
+  "use of placement new requires explicit declaration">;
+
 // MIG routine annotations.
 def warn_mig_server_routine_does_not_return_kern_return_t : Warning<
   "'mig_server_routine' attribute only applies to routines that return a kern_return_t">,
diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index b59f3faa6e..32b35ba7c3 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -2413,7 +2413,11 @@ bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
     }
 
     if (getLangOpts().OpenCLCPlusPlus && R.empty()) {
-      Diag(StartLoc, diag::err_openclcxx_not_supported) << "default new";
+      if (PlaceArgs.empty()) {
+        Diag(StartLoc, diag::err_openclcxx_not_supported) << "default new";
+      } else {
+        Diag(StartLoc, diag::err_openclcxx_placement_new);
+      }
       return true;
     }
 
diff --git a/test/SemaOpenCLCXX/newdelete.cl b/test/SemaOpenCLCXX/newdelete.cl
index ce6273f3be..14be4550c0 100644
--- a/test/SemaOpenCLCXX/newdelete.cl
+++ b/test/SemaOpenCLCXX/newdelete.cl
@@ -21,7 +21,7 @@ class B {
 void test_default_new_delete(void *buffer, A **pa) {
   A *a = new A;         // expected-error {{'default new' is not supported in OpenCL C++}}
   delete a;             // expected-error {{'default delete' is not supported in OpenCL C++}}
-  *pa = new (buffer) A; // expected-error {{'default new' is not supported in OpenCL C++}}
+  *pa = new (buffer) A; // expected-error {{use of placement new requires explicit declaration}}
 }
 
 // expected-note@+1 {{candidate function not viable: requires 2 arguments, but 1 was provided}}