From 83be12c8638a5136b937e602b3a9e25f4bc8e50d Mon Sep 17 00:00:00 2001 From: Eli Friedman Date: Thu, 12 Jan 2012 23:48:56 +0000 Subject: [PATCH] Recommit r148056 with fixes to deal with weirdness with bitfields in unions. Original message: Make sure adding a field to a struct never reduces its size. PR11745. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@148070 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/AST/RecordLayoutBuilder.cpp | 8 ++++---- test/SemaCXX/empty-class-layout.cpp | 11 +++++++++++ 2 files changed, 15 insertions(+), 4 deletions(-) diff --git a/lib/AST/RecordLayoutBuilder.cpp b/lib/AST/RecordLayoutBuilder.cpp index 43dee104ba..5223219a30 100644 --- a/lib/AST/RecordLayoutBuilder.cpp +++ b/lib/AST/RecordLayoutBuilder.cpp @@ -1869,12 +1869,12 @@ void RecordLayoutBuilder::LayoutField(const FieldDecl *D) { // Reserve space for this field. uint64_t FieldSizeInBits = Context.toBits(FieldSize); if (IsUnion) - setSize(std::max(getSizeInBits(), FieldSizeInBits)); + setDataSize(std::max(getDataSizeInBits(), FieldSizeInBits)); else - setSize(FieldOffset + FieldSize); + setDataSize(FieldOffset + FieldSize); - // Update the data size. - setDataSize(getSizeInBits()); + // Update the size. + setSize(std::max(getSizeInBits(), getDataSizeInBits())); // Remember max struct/class alignment. UpdateAlignment(FieldAlign, UnpackedFieldAlign); diff --git a/test/SemaCXX/empty-class-layout.cpp b/test/SemaCXX/empty-class-layout.cpp index 0b46bf045a..c68f2bb6fb 100644 --- a/test/SemaCXX/empty-class-layout.cpp +++ b/test/SemaCXX/empty-class-layout.cpp @@ -144,3 +144,14 @@ struct B : Empty, A { }; SA(0, sizeof(B) == 16); } + +namespace Test7 { + // Make sure we reserve enough space for both bases; PR11745. + struct Empty { }; + struct Base1 : Empty { }; + struct Base2 : Empty { }; + struct Test : Base1, Base2 { + char c; + }; + SA(0, sizeof(Test) == 2); +} -- 2.50.1