llvm-project/clang/test/CodeGenCXX/pragma-pack-3.cpp

// RUN: %clang_cc1 %s -triple=i686-apple-darwin10 -emit-llvm -o - | FileCheck %s

struct Base {
  char a;
};

struct Derived_1 : virtual Base
{
  char b;
};

#pragma pack(1)
struct Derived_2 : Derived_1 {
  // CHECK: %struct.Derived_2 = type { %struct.Derived_1.base, %struct.Base }
  // CHECK: %struct.Derived_1.base = type <{ ptr, i8 }>
};

Derived_2 x;
[CodeGenCXX] Convert some tests to opaque pointers (NFC) Conversion done using the script at https://gist.github.com/nikic/98357b71fd67756b0f064c9517b62a34. These are tests where the conversion worked out of the box and no manual fixup was performed. 2022-10-06 12:12:57 +02:00			`// RUN: %clang_cc1 %s -triple=i686-apple-darwin10 -emit-llvm -o - \| FileCheck %s`
Fixing PR18510 by checking whether the non-virtual base of the derived class might have a smaller size as compared to the stand-alone type of the base class. This is possible when the derived class is packed and hence might have smaller alignment requirement than the base class. Differential Revision: http://llvm-reviews.chandlerc.com/D2599 llvm-svn: 200031 2014-01-24 19:28:24 +00:00
			`struct Base {`
			`char a;`
			`};`

			`struct Derived_1 : virtual Base`
			`{`
			`char b;`
			`};`

			`#pragma pack(1)`
			`struct Derived_2 : Derived_1 {`
Complete Rewrite of CGRecordLayoutBuilder CGRecordLayoutBuilder was aging, complex, multi-pass, and shows signs of existing before ASTRecordLayoutBuilder. It redundantly performed many layout operations that are now performed by ASTRecordLayoutBuilder and asserted that the results were the same. With the addition of support for the MS-ABI, such as placement of vbptrs, vtordisps, different bitfield layout and a variety of other features, CGRecordLayoutBuilder was growing unwieldy in its redundancy. This patch re-architects CGRecordLayoutBuilder to not perform any redundant layout but rather, as directly as possible, lower an ASTRecordLayout to an llvm::type. The new architecture is significantly smaller and simpler than the CGRecordLayoutBuilder and contains fewer ABI-specific code paths. It's also one pass. The architecture of the new system is described in the comments. For the most part, the new system simply takes all of the fields and bases from an ASTRecordLayout, sorts them, inserts padding and dumps a record. Bitfields, unions and primary virtual bases make this process a bit more complicated. See the inline comments. In addition, this patch updates a few lit tests due to the fact that the new system computes more accurate llvm types than CGRecordLayoutBuilder. Each change is commented individually in the review. Differential Revision: http://llvm-reviews.chandlerc.com/D2795 llvm-svn: 201907 2014-02-21 23:49:50 +00:00			`// CHECK: %struct.Derived_2 = type { %struct.Derived_1.base, %struct.Base }`
[CodeGenCXX] Convert some tests to opaque pointers (NFC) Conversion done using the script at https://gist.github.com/nikic/98357b71fd67756b0f064c9517b62a34. These are tests where the conversion worked out of the box and no manual fixup was performed. 2022-10-06 12:12:57 +02:00			`// CHECK: %struct.Derived_1.base = type <{ ptr, i8 }>`
Fixing PR18510 by checking whether the non-virtual base of the derived class might have a smaller size as compared to the stand-alone type of the base class. This is possible when the derived class is packed and hence might have smaller alignment requirement than the base class. Differential Revision: http://llvm-reviews.chandlerc.com/D2599 llvm-svn: 200031 2014-01-24 19:28:24 +00:00			`};`

			`Derived_2 x;`