---

yaml
---
r: 319398
b: refs/heads/master-rebranch
c: 9e87e49
h: refs/heads/master

Author: swift-ci

[refs]

@@ -1457,4 +1457,4 @@ refs/tags/swift-DEVELOPMENT-SNAPSHOT-2019-08-02-a: ddd2b2976aa9bfde5f20fe37f6bd2
 refs/tags/swift-DEVELOPMENT-SNAPSHOT-2019-08-03-a: 171cc166f2abeb5ca2a4003700a8a78a108bd300
 refs/heads/benlangmuir-patch-1: baaebaf39d52f3bf36710d4fe40cf212e996b212
 refs/heads/i-do-redeclare: 8c4e6d5de5c1e3f0a2cedccf319df713ea22c48e
-refs/heads/master-rebranch: ee810d21dfc09e4e445cb6a6d70b55060b465c7b
+refs/heads/master-rebranch: 9e87e491c68a514f48741d9ba249f677ef83eace

branches/master-rebranch/lib/Parse/ParseIfConfig.cpp

@@ -17,6 +17,7 @@
 #include "swift/Parse/Parser.h"
 
 #include "swift/AST/ASTVisitor.h"
+#include "swift/AST/DiagnosticSuppression.h"
 #include "swift/Basic/Defer.h"
 #include "swift/Basic/LangOptions.h"
 #include "swift/Basic/Version.h"
@@ -638,6 +639,12 @@ ParserResult<IfConfigDecl> Parser::parseIfConfig(
     SmallVector<ASTNode, 16> Elements;
     if (isActive || !isVersionCondition) {
       parseElements(Elements, isActive);
+    } else if (SyntaxContext->isEnabled()) {
+      // We shouldn't skip code if we are building syntax tree.
+      // The parser will keep running and we just discard the AST part.
+      DiagnosticSuppression suppression(Context.Diags);
+      SmallVector<ASTNode, 16> dropedElements;
+      parseElements(dropedElements, false);
     } else {
       DiagnosticTransaction DT(Diags);
       skipUntilConditionalBlockClose();

branches/master-rebranch/test/Syntax/diagnostics_verify.swift

@@ -19,3 +19,10 @@ class { // expected-error {{unknown declaration syntax exists in the source}}
   // expected-error@-4 {{top-level statement cannot begin with a closure expression}}
 
 }
+
+#if swift(<1)
+print("Wat")
+class { // expected-error {{unknown declaration syntax exists in the source}}
+
+}
+#endif