[cxx1z-constexpr-lambda] Make a lambda's closure type eligible as a literal-type in C++1z

Additionally, for pre-C++1z, instead of forbidding a lambda's closure type from being a literal type through circumlocutorily setting HasNonLiteralTypeFieldsOrBases falsely to true -- handle lambda's more directly in CXXRecordDecl::isLiteral().

One additional small step towards implementing constexpr-lambdas.

Thanks to Richard Smith for his review! 
https://reviews.llvm.org/D22662

llvm-svn: 276514

1 files changed, 15 insertions, 3 deletions

diff --git a/clang/test/SemaCXX/cxx1z-constexpr-lambdas.cpp b/clang/test/SemaCXX/cxx1z-constexpr-lambdas.cpp
index 8e7657fb6e8..610d8144437 100644
--- a/clang/test/SemaCXX/cxx1z-constexpr-lambdas.cpp
+++ b/clang/test/SemaCXX/cxx1z-constexpr-lambdas.cpp
@@ -1,8 +1,8 @@
 // RUN: %clang_cc1 -std=c++1z -verify -fsyntax-only -fblocks %s
 // RUN: %clang_cc1 -std=c++1z -verify -fsyntax-only -fblocks -fdelayed-template-parsing %s 
-// RUN: %clang_cc1 -std=c++1z -verify -fsyntax-only -fblocks -fms-extensions %s 
-// RUN: %clang_cc1 -std=c++1z -verify -fsyntax-only -fblocks -fdelayed-template-parsing -fms-extensions %s 
+// RUN: %clang_cc1 -std=c++14 -verify -fsyntax-only -fblocks %s -DCPP14_AND_EARLIER
 
+#ifndef CPP14_AND_EARLIER
 namespace test_constexpr_checking {
 
 namespace ns1 {
@@ -33,4 +33,16 @@ namespace ns3 {
       L(3); //expected-note{{non-constexpr function}}
 } 
 
-} // end ns test_constexpr_call
\ No newline at end of file
+} // end ns test_constexpr_call
+
+#endif
+
+namespace test_lambda_is_literal {
+#ifdef CPP14_AND_EARLIER
+//expected-error@+4{{not a literal type}}
+//expected-note@+2{{not an aggregate and has no constexpr constructors}}
+#endif
+auto L = [] { };
+constexpr int foo(decltype(L) l) { return 0; }
+
+}
\ No newline at end of file