3 files changed, 44 insertions, 2 deletions
diff --git a/src/passes/MemoryPacking.cpp b/src/passes/MemoryPacking.cpp
index 4a183e7d7..27168942a 100644
--- a/src/passes/MemoryPacking.cpp
+++ b/src/passes/MemoryPacking.cpp
@@ -514,10 +514,16 @@ void MemoryPacking::createReplacements(Module* module,
     size_t start = init->offset->cast<Const>()->value.geti32();
     size_t end = start + init->size->cast<Const>()->value.geti32();
 
+    // Segment index used in emitted memory.init instructions
+    size_t initIndex = segmentIndex;
+
     // Index of the range from which this memory.init starts reading
     size_t firstRangeIdx = 0;
     while (firstRangeIdx < ranges.size() &&
            ranges[firstRangeIdx].end <= start) {
+      if (!ranges[firstRangeIdx].isZero) {
+        ++initIndex;
+      }
       ++firstRangeIdx;
     }
 
@@ -568,7 +574,6 @@ void MemoryPacking::createReplacements(Module* module,
 
     size_t bytesWritten = 0;
 
-    size_t initIndex = segmentIndex;
     for (size_t i = firstRangeIdx; i < ranges.size() && ranges[i].start < end;
          ++i) {
       auto& range = ranges[i];
diff --git a/test/passes/memory-packing_all-features.txt b/test/passes/memory-packing_all-features.txt
index af18ea25f..bc9139f74 100644
--- a/test/passes/memory-packing_all-features.txt
+++ b/test/passes/memory-packing_all-features.txt
@@ -1505,3 +1505,27 @@
   )
  )
 )
+(module
+ (type $none_=>_none (func))
+ (import "env" "memory" (memory $mimport$0 1 1))
+ (data passive "skipped")
+ (data passive "included")
+ (global $__mem_segment_drop_state_0 (mut i32) (i32.const 0))
+ (export "func_54" (func $0))
+ (func $0
+  (if
+   (global.get $__mem_segment_drop_state_0)
+   (unreachable)
+  )
+  (memory.fill
+   (i32.const 0)
+   (i32.const 0)
+   (i32.const 30)
+  )
+  (memory.init 1
+   (i32.const 30)
+   (i32.const 0)
+   (i32.const 8)
+  )
+ )
+)
diff --git a/test/passes/memory-packing_all-features.wast b/test/passes/memory-packing_all-features.wast
index 309ee79ad..3ee0bd5e7 100644
--- a/test/passes/memory-packing_all-features.wast
+++ b/test/passes/memory-packing_all-features.wast
@@ -494,4 +494,17 @@
     )
     (data.drop 0)
   )
-)
-\ No newline at end of file
+)
+
+(module
+ (import "env" "memory" (memory 1 1))
+ (data passive "skipped\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00included")
+ (export "func_54" (func $0))
+ (func $0
+  (memory.init 0
+   (i32.const 0)
+   (i32.const 7)
+   (i32.const 38)
+  )
+ )
+)