diff --git a/flang/lib/Lower/Allocatable.cpp b/flang/lib/Lower/Allocatable.cpp
--- a/flang/lib/Lower/Allocatable.cpp
+++ b/flang/lib/Lower/Allocatable.cpp
@@ -572,10 +572,10 @@
     if (alloc.type.IsPolymorphic())
       genRuntimeAllocateApplyMold(builder, loc, box, sourceExv,
                                   alloc.getSymbol().Rank());
-    genSetDeferredLengthParameters(alloc, box);
     genAllocateObjectBounds(alloc, box);
     mlir::Value stat =
         genRuntimeAllocateSource(builder, loc, box, sourceExv, errorManager);
+    genSetDeferredLengthParameters(alloc, box);
     fir::factory::syncMutableBoxFromIRBox(builder, loc, box);
     errorManager.assignStat(builder, loc, stat);
   }