---

yaml
---
r: 15659
b: refs/heads/try
c: bbc4a74
h: refs/heads/master
i:
  15657: 0b4cd38
  15655: 24b3a6c
v: v3

Author: brson

[refs]

@@ -2,5 +2,5 @@
 refs/heads/master: 61b1875c16de39c166b0f4d54bba19f9c6777d1a
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
 refs/heads/snap-stage3: 4a81779abd786ff22d71434c6d9a5917ea4cdfff
-refs/heads/try: 8e15640adacd1f0cab8617d62f445024915e5214
+refs/heads/try: bbc4a74dc685a570ebdf53849e8cc2220ed1d586
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105

branches/try/src/rt/rust_shape.h

@@ -123,6 +123,18 @@ rust_alignof<double>() {
     return 4;
 }
 
+// Issue #2303
+// On 32-bit x86 the alignment of 64-bit ints in structures is 4 bytes
+// Which is different from the preferred 8-byte alignment reported
+// by __alignof__ (at least on gcc).
+#ifdef __i386__
+template<>
+inline size_t
+rust_alignof<uint64_t>() {
+    return 4;
+}
+#endif
+
 
 // Utility classes
 

branches/try/src/test/run-pass/rec-align-32-bit.rs

@@ -0,0 +1,45 @@
+// xfail-pretty
+// Issue #2303
+
+// This is the type with the questionable alignment
+type inner = {
+    c64: u64
+};
+
+// This is the type that contains the type with the
+// questionable alignment, for testing
+type outer = {
+    c8: u8,
+    t: inner
+};
+
+#[cfg(target_arch = "x86")]
+fn main() {
+
+    let x = {c8: 22u8, t: {c64: 44u64}};
+
+    // Send it through the shape code
+    let y = #fmt["%?", x];
+
+    #debug("align inner = %?", sys::align_of::<inner>()); // 8
+    #debug("size outer = %?", sys::size_of::<outer>());   // 12
+    #debug("y = %s", y);                                  // (22, (0))
+
+    // per clang/gcc the alignment of `inner` is 4 on x86.
+    // we say it's 8
+    //assert sys::align_of::<inner>() == 4u; // fails
+
+    // per clang/gcc the size of `outer` should be 12
+    // because `inner`s alignment was 4.
+    // LLVM packs the struct the way clang likes, despite
+    // our intents regarding the alignment of `inner` and
+    // we end up with the same size `outer` as clang
+    assert sys::size_of::<outer>() == 12u; // passes
+
+    // But now our shape code doesn't find the inner struct
+    // We print (22, (0))
+    assert y == "(22, (44))"; // fails
+}
+
+#[cfg(target_arch = "x86_64")]
+fn main() { }