MS ABI: Bitfields FielDecls only align if they allocate

Don't consider a __declspec(align) on a bitfield's declaration if it didn't
allocate any underlying storage.

This fixes PR19414.

llvm-svn: 206132

1 files changed, 24 insertions, 2 deletions

diff --git a/clang/test/Sema/ms_bitfield_layout.c b/clang/test/Sema/ms_bitfield_layout.c
index f2010c16225..8444f469d59 100644
--- a/clang/test/Sema/ms_bitfield_layout.c
+++ b/clang/test/Sema/ms_bitfield_layout.c
@@ -1,6 +1,6 @@
-// RUN: %clang_cc1 -fno-rtti -emit-llvm-only -triple i686-pc-win32 -fdump-record-layouts %s 2>/dev/null \

+// RUN: %clang_cc1 -fno-rtti -emit-llvm-only -triple i686-pc-win32 -fms-extensions -fdump-record-layouts %s 2>/dev/null \

 // RUN:            | FileCheck %s

-// RUN: %clang_cc1 -fno-rtti -emit-llvm-only -triple x86_64-pc-win32 -fdump-record-layouts %s 2>/dev/null \

+// RUN: %clang_cc1 -fno-rtti -emit-llvm-only -triple x86_64-pc-win32 -fms-extensions -fdump-record-layouts %s 2>/dev/null \

 // RUN:            | FileCheck %s

 

 typedef struct A {

@@ -111,6 +111,16 @@ typedef struct H {
 // CHECK:   Alignment:16

 // CHECK:   FieldOffsets: [0, 16, 16, 16]>

 

+typedef struct I {

+	short : 8;

+	__declspec(align(16)) short : 8;

+} I;

+

+// CHECK: Type: struct I

+// CHECK:   Size:16

+// CHECK:   Alignment:16

+// CHECK:   FieldOffsets: [0, 8]

+

 #pragma pack(push, 1)

 

 typedef struct A1 {

@@ -221,6 +231,16 @@ typedef struct H1 {
 // CHECK:   Alignment:8

 // CHECK:   FieldOffsets: [0, 32, 32, 32]>

 

+typedef struct I1 {

+	short : 8;

+	__declspec(align(16)) short : 8;

+} I1;

+

+// CHECK: Type: struct I1

+// CHECK:   Size:16

+// CHECK:   Alignment:8

+// CHECK:   FieldOffsets: [0, 8]

+

 #pragma pack(pop)

 

 int x[

@@ -232,6 +252,7 @@ sizeof(E ) +
 sizeof(F ) +

 sizeof(G ) +

 sizeof(H ) +

+sizeof(I ) +

 sizeof(A1) +

 sizeof(B1) +

 sizeof(C1) +

@@ -240,4 +261,5 @@ sizeof(E1) +
 sizeof(F1) +

 sizeof(G1) +

 sizeof(H1) +

+sizeof(I1) +

 0];