diff --git a/src/comp/back/x86.rs b/src/comp/back/x86.rs
index 94243c36cba..ac52fca5baf 100644
--- a/src/comp/back/x86.rs
+++ b/src/comp/back/x86.rs
@@ -157,6 +157,26 @@ fn get_module_asm() -> str {
     ret _str.connect(glues, "\n\n");
 }
 
+fn get_data_layout() -> str {
+    if (_str.eq(target_os(), "macos")) {
+      ret "e-p:32:32-f64:32:64-i64:32:64-f80:128:128-n8:16:32";
+    }
+    if (_str.eq(target_os(), "win32")) {
+      ret "e-p:32:32-f64:64:64-i64:64:64-f80:32:32-n8:16:32";
+    }
+    ret "e-p:32:32-f64:32:64-i64:32:64-f80:32:32-n8:16:32";
+}
+
+fn get_target_triple() -> str {
+    if (_str.eq(target_os(), "macos")) {
+        ret "i686-apple-darwin";
+    }
+    if (_str.eq(target_os(), "win32")) {
+        ret "i686-pc-mingw32";
+    }
+    ret "i686-pc-linux-gnu";
+}
+
 
 //
 // Local Variables:
diff --git a/src/comp/middle/trans.rs b/src/comp/middle/trans.rs
index 2b4bec0c7ab..9b6fa0abad9 100644
--- a/src/comp/middle/trans.rs
+++ b/src/comp/middle/trans.rs
@@ -2151,6 +2151,9 @@ fn trans_crate(session.session sess, @ast.crate crate, str output) {
         llvm.LLVMModuleCreateWithNameInContext(_str.buf("rust_out"),
                                                llvm.LLVMGetGlobalContext());
 
+    llvm.LLVMSetDataLayout(llmod, _str.buf(x86.get_data_layout()));
+    llvm.LLVMSetTarget(llmod, _str.buf(x86.get_target_triple()));
+
     llvm.LLVMSetModuleInlineAsm(llmod, _str.buf(x86.get_module_asm()));
 
     auto intrinsics = declare_intrinsics(llmod);