PR3062: statement expressions should be illegal at file scope.  I don't 
think this has any significant effects at the moment, but it could 
matter if we start constant-folding statement expressions like gcc does.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@62943 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index d4babb4..1d55ed7 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -3940,6 +3940,11 @@
   assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!");
   CompoundStmt *Compound = cast<CompoundStmt>(SubStmt);
 
+  bool isFileScope = getCurFunctionOrMethodDecl() == 0;
+  if (isFileScope) {
+    return Diag(LPLoc, diag::err_stmtexpr_file_scope);
+  }
+
   // FIXME: there are a variety of strange constraints to enforce here, for
   // example, it is not possible to goto into a stmt expression apparently.
   // More semantic analysis is needed.