Add upcall_rust_personality

This just wraps __gxx_personality_v0 with our upcall naming convention

Issue #236

src/comp/back/upcall.rs

@@ -37,7 +37,8 @@ type upcalls =
      log_type: ValueRef,
      dynastack_mark: ValueRef,
      dynastack_alloc: ValueRef,
-     dynastack_free: ValueRef};
+     dynastack_free: ValueRef,
+     rust_personality: ValueRef};
 
 fn declare_upcalls(_tn: type_names, tydesc_type: TypeRef,
                    taskptr_type: TypeRef, llmod: ModuleRef) -> @upcalls {
@@ -89,7 +90,9 @@ fn declare_upcalls(_tn: type_names, tydesc_type: TypeRef,
           dynastack_alloc:
               d("dynastack_alloc_2", [T_size_t(), T_ptr(tydesc_type)],
                 T_ptr(T_i8())),
-          dynastack_free: d("dynastack_free", [T_ptr(T_i8())], T_void())};
+          dynastack_free: d("dynastack_free", [T_ptr(T_i8())], T_void()),
+          rust_personality: dr("rust_personality", [], T_i32())
+         };
 }
 //
 // Local Variables:

src/rt/rust_upcall.cpp

@@ -1,6 +1,8 @@
 #include "rust_gc.h"
 #include "rust_internal.h"
 #include "rust_upcall.h"
+#include <stdint.h>
+#include <unwind.h>
 
 // Upcalls.
 
@@ -190,6 +192,26 @@ upcall_dynastack_free(rust_task *task, void *ptr) {
     return task->dynastack.free(ptr);
 }
 
+extern "C" _Unwind_Reason_Code
+__gxx_personality_v0(int version,
+                     _Unwind_Action actions,
+                     uint64_t exception_class,
+                     _Unwind_Exception *ue_header,
+                     _Unwind_Context *context);
+
+extern "C" _Unwind_Reason_Code
+upcall_rust_personality(int version,
+                        _Unwind_Action actions,
+                        uint64_t exception_class,
+                        _Unwind_Exception *ue_header,
+                        _Unwind_Context *context) {
+    return __gxx_personality_v0(version,
+                                actions,
+                                exception_class,
+                                ue_header,
+                                context);
+}
+
 //
 // Local Variables:
 // mode: C++

src/rt/rustrt.def.in

@@ -78,5 +78,6 @@ upcall_vec_grow
 upcall_vec_push
 upcall_log_type
 upcall_malloc
+upcall_rust_personality
 upcall_shared_malloc
 upcall_shared_free