[clang] [clang] Implement gcc_struct attribute on Itanium targets (PR #71148)

[Eli Friedman via cfe-commits]

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@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 -emit-llvm-only -triple x86_64-pc-linux-gnu %s
+// RUN: %clang_cc1 -emit-llvm-only -triple x86_64-pc-linux-gnu -fms-layout-compatibility=microsoft %s
+// RUN: %clang_cc1 -emit-llvm-only -triple x86_64-pc-windows-gnu %s
+// RUN: %clang_cc1 -emit-llvm-only -triple x86_64-pc-windows-gnu -fms-layout-compatibility=itanium %s
+
+struct {
+    int a : 24;
+    char b : 8;
+} __attribute__((gcc_struct)) t1;
+static int a1[(sizeof(t1) == 4) - 1];
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efriedma-quic wrote:

static_assert

https://github.com/llvm/llvm-project/pull/71148