DWARF and unwind support for AOT assembly output.

runtime/vm/datastream.h

Index: runtime/vm/datastream.h
diff --git a/runtime/vm/datastream.h b/runtime/vm/datastream.h
index 3e9a6c0d7e4b9476c3460b3299167905215af4b0..5a43bd5917c7f469312eb9ccf149f516a991df4b 100644
--- a/runtime/vm/datastream.h
+++ b/runtime/vm/datastream.h
@@ -388,6 +388,29 @@ class WriteStream : public ValueObject {
     va_list args;
     va_start(args, format);
     VPrint(format, args);
+    va_end(args);
+  }
+
+  void VPrint(const char* format, va_list args) {
+    // Measure.
+    va_list measure_args;
+    va_copy(measure_args, args);
+    intptr_t len = OS::VSNPrint(NULL, 0, format, measure_args);
+    va_end(measure_args);
+
+    // Alloc.
+    if ((end_ - current_) < (len + 1)) {
+      Resize(len + 1);
+    }
+    ASSERT((end_ - current_) >= (len + 1));
+
+    // Print.
+    va_list print_args;
+    va_copy(print_args, args);
+    OS::VSNPrint(reinterpret_cast<char*>(current_), len + 1, format,
+                 print_args);
+    va_end(print_args);
+    current_ += len;  // Not len + 1 to swallow the terminating NUL.
   }
 
   template <typename T>
@@ -428,28 +451,6 @@ class WriteStream : public ValueObject {
     ASSERT(end_ > *buffer_);
   }
 
-  void VPrint(const char* format, va_list args) {
-    // Measure.
-    va_list measure_args;
-    va_copy(measure_args, args);
-    intptr_t len = OS::VSNPrint(NULL, 0, format, measure_args);
-    va_end(measure_args);
-
-    // Alloc.
-    if ((end_ - current_) < (len + 1)) {
-      Resize(len + 1);
-    }
-    ASSERT((end_ - current_) >= (len + 1));
-
-    // Print.
-    va_list print_args;
-    va_copy(print_args, args);
-    OS::VSNPrint(reinterpret_cast<char*>(current_), len + 1, format,
-                 print_args);
-    va_end(print_args);
-    current_ += len;  // Not len + 1 to swallow the terminating NUL.
-  }
-
  private:
   uint8_t** const buffer_;
   uint8_t* end_;