Add missing warning for use of C++1z init-statements in C++14 and before.

llvm-svn: 284530

diff --git a/clang/include/clang/Basic/DiagnosticParseKinds.td b/clang/include/clang/Basic/DiagnosticParseKinds.td
index fd9c962..b5b9055 100644 (file)
--- a/clang/include/clang/Basic/DiagnosticParseKinds.td
+++ b/clang/include/clang/Basic/DiagnosticParseKinds.td
@@ -521,6 +521,12 @@ def ext_constexpr_if : ExtWarn<
 def warn_cxx14_compat_constexpr_if : Warning<
   "constexpr if is incompatible with C++ standards before C++1z">,
   DefaultIgnore, InGroup<CXXPre1zCompat>;
+def ext_init_statement : ExtWarn<
+  "'%select{if|switch}0' initialization statements are a C++1z extension">,
+  InGroup<CXX1z>;
+def warn_cxx14_compat_init_statement : Warning<
+  "%select{if|switch}0 initialization statements are incompatible with "
+  "C++ standards before C++1z">, DefaultIgnore, InGroup<CXXPre1zCompat>;
 
 // C++ derived classes
 def err_dup_virtual : Error<"duplicate 'virtual' in base specifier">;

diff --git a/clang/lib/Parse/ParseExprCXX.cpp b/clang/lib/Parse/ParseExprCXX.cpp
index 614ba8f..83e6ae4 100644 (file)
--- a/clang/lib/Parse/ParseExprCXX.cpp
+++ b/clang/lib/Parse/ParseExprCXX.cpp
@@ -1787,6 +1787,10 @@ Sema::ConditionResult Parser::ParseCXXCondition(StmtResult *InitStmt,
   }
 
   case ConditionOrInitStatement::InitStmtDecl: {
+    Diag(Tok.getLocation(), getLangOpts().CPlusPlus1z
+                                ? diag::warn_cxx14_compat_init_statement
+                                : diag::ext_init_statement)
+        << (CK == Sema::ConditionKind::Switch);
     SourceLocation DeclStart = Tok.getLocation(), DeclEnd;
     DeclGroupPtrTy DG = ParseSimpleDeclaration(
         Declarator::InitStmtContext, DeclEnd, attrs, /*RequireSemi=*/true);

diff --git a/clang/test/SemaCXX/warn-c++1z-extensions.cpp b/clang/test/SemaCXX/warn-c++1z-extensions.cpp
new file mode 100644 (file)
index 0000000..9b5e1c2
--- /dev/null
+++ b/clang/test/SemaCXX/warn-c++1z-extensions.cpp
@@ -0,0 +1,8 @@
+// RUN: %clang_cc1 -fsyntax-only -std=c++14 -verify %s
+
+void f() {
+  if (bool b = true; b) {} // expected-warning {{'if' initialization statements are a C++1z extension}}
+  switch (int n = 5; n) { // expected-warning {{'switch' initialization statements are a C++1z extension}}
+  case 5: break;
+  }
+}