Honor __unaligned in codegen for declarations and expressions

This patch honors the unaligned type qualifier (currently available through he
keyword __unaligned and -fms-extensions) in CodeGen. In the current form the
patch affects declarations and expressions. It does not affect fields of
classes.

Differential Revision: https://reviews.llvm.org/D30166

llvm-svn: 297276

1 files changed, 17 insertions, 0 deletions

diff --git a/clang/test/CodeGen/unaligned-field.c b/clang/test/CodeGen/unaligned-field.c
new file mode 100644
index 00000000000..5aa59c27991
--- /dev/null
+++ b/clang/test/CodeGen/unaligned-field.c
@@ -0,0 +1,17 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fms-extensions -emit-llvm < %s | FileCheck %s
+// Test that __unaligned does not impact the layout of the fields.
+
+struct A
+{
+    char a;
+    __unaligned int b;
+} a;
+// CHECK: %struct.A = type { i8, i32 }
+
+struct A2
+{
+    int b;
+    char a;
+    __unaligned int c;
+} a2;
+// CHECK: %struct.A2 = type { i32, i8, i32 }