[c++2a] P0683R1: Permit default member initializers for bit-fields.

This would be trivial, except that our in-memory and serialized representations
for FieldDecls assumed that this can't happen.

llvm-svn: 311867

1 files changed, 10 insertions, 9 deletions

diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp
index 085341571ce..37cce8f507a 100644
--- a/clang/lib/Serialization/ASTReaderDecl.cpp
+++ b/clang/lib/Serialization/ASTReaderDecl.cpp
@@ -1219,16 +1219,17 @@ void ASTDeclReader::VisitObjCPropertyImplDecl(ObjCPropertyImplDecl *D) {
 void ASTDeclReader::VisitFieldDecl(FieldDecl *FD) {
   VisitDeclaratorDecl(FD);
   FD->Mutable = Record.readInt();
-  if (int BitWidthOrInitializer = Record.readInt()) {
-    FD->InitStorage.setInt(
-          static_cast<FieldDecl::InitStorageKind>(BitWidthOrInitializer - 1));
-    if (FD->InitStorage.getInt() == FieldDecl::ISK_CapturedVLAType) {
-      // Read captured variable length array.
-      FD->InitStorage.setPointer(Record.readType().getAsOpaquePtr());
-    } else {
-      FD->InitStorage.setPointer(Record.readExpr());
-    }
+
+  if (auto ISK = static_cast<FieldDecl::InitStorageKind>(Record.readInt())) {
+    FD->InitStorage.setInt(ISK);
+    FD->InitStorage.setPointer(ISK == FieldDecl::ISK_CapturedVLAType
+                                   ? Record.readType().getAsOpaquePtr()
+                                   : Record.readExpr());
   }
+
+  if (auto *BW = Record.readExpr())
+    FD->setBitWidth(BW);
+
   if (!FD->getDeclName()) {
     if (FieldDecl *Tmpl = ReadDeclAs<FieldDecl>())
       Reader.getContext().setInstantiatedFromUnnamedFieldDecl(FD, Tmpl);