diff --git a/lib/MC/MCAssembler.cpp b/lib/MC/MCAssembler.cpp
index f0e1d7f..8db1536 100644
--- a/lib/MC/MCAssembler.cpp
+++ b/lib/MC/MCAssembler.cpp
@@ -447,7 +447,7 @@
 
     // FIXME: We need a way to communicate this error.
     int64_t Offset = TargetLocation - FragmentOffset;
-    if (Offset < 0)
+    if (Offset < 0 || Offset >= 0x40000000)
       report_fatal_error("invalid .org offset '" + Twine(TargetLocation) +
                          "' (at offset '" + Twine(FragmentOffset) + "'");