Teach overload resolution to prefer user-defined conversion via a

lambda closure type's function pointer conversion over user-defined
conversion via a lambda closure type's block pointer conversion,
always. This is a preference for more-standard code (since blocks
are an extension)  and a nod to efficiency, since function pointers
don't require any memory management. Fixes PR12063.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@151170 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 31 insertions, 0 deletions

diff --git a/test/CXX/expr/expr.prim/expr.prim.lambda/blocks.mm b/test/CXX/expr/expr.prim/expr.prim.lambda/blocks.mm
index f6a8db23e9..0c3fdb2d80 100644
--- a/test/CXX/expr/expr.prim/expr.prim.lambda/blocks.mm
+++ b/test/CXX/expr/expr.prim/expr.prim.lambda/blocks.mm
@@ -55,3 +55,34 @@ void nesting() {
     }();
   }();
 }
+
+namespace overloading {
+  void bool_conversion() {
+    if ([](){}) {
+    }
+
+    bool b = []{};
+    b = (bool)[]{};
+  }
+
+  void conversions() {
+    int (*fp)(int) = [](int x) { return x + 1; };
+    fp = [](int x) { return x + 1; };
+
+    typedef int (*func_ptr)(int);
+    fp = (func_ptr)[](int x) { return x + 1; };
+
+    int (^bp)(int) = [](int x) { return x + 1; };
+    bp = [](int x) { return x + 1; };
+
+    typedef int (^block_ptr)(int);
+    bp = (block_ptr)[](int x) { return x + 1; };
+  }
+
+  int &accept_lambda_conv(int (*fp)(int));
+  float &accept_lambda_conv(int (^bp)(int));
+
+  void call_with_lambda() {
+    int &ir = accept_lambda_conv([](int x) { return x + 1; });
+  }
+}