commit a625da716c8300d2ff9ec2313e7b38892bcfcfcb
author Richard Smith <richard-llvm@metafoo.co.uk> Mon Jul 29 19:59:45 2019 +0000
committer Richard Smith <richard-llvm@metafoo.co.uk> Mon Jul 29 19:59:45 2019 +0000
tree 9f9e3b53c77485cbd63f9c9b6ba5f69d8ce92e50
parent 8e9516f2aa495749edd2adb7c8fe0778ee462c17

When determining whether a lambda-expression is implicitly constexpr,
check the formal rules rather than seeing if the normal checks produce a
diagnostic.

This fixes the handling of C++2a extensions in lambdas in C++17 mode,
as well as some corner cases in earlier language modes where we issue
diagnostics for things other than not satisfying the formal constexpr
requirements.

llvm-svn: 367254

clang/lib/Sema/SemaLambda.cpp

diff --git a/clang/lib/Sema/SemaLambda.cpp b/clang/lib/Sema/SemaLambda.cpp
index 986524e..e7c51a3 100644
--- a/clang/lib/Sema/SemaLambda.cpp
+++ b/clang/lib/Sema/SemaLambda.cpp
@@ -1776,10 +1776,9 @@
       !CallOperator->isConstexpr() &&
       !isa<CoroutineBodyStmt>(CallOperator->getBody()) &&
       !Class->getDeclContext()->isDependentContext()) {
-    TentativeAnalysisScope DiagnosticScopeGuard(*this);
     CallOperator->setConstexprKind(
-        (CheckConstexprFunctionDecl(CallOperator) &&
-         CheckConstexprFunctionBody(CallOperator, CallOperator->getBody()))
+        CheckConstexprFunctionDefinition(CallOperator,
+                                         CheckConstexprKind::CheckValid)
             ? CSK_constexpr
             : CSK_unspecified);
   }