5 files changed, 41 insertions, 10 deletions
diff --git a/src/ir/table-utils.cpp b/src/ir/table-utils.cpp
index fb9285319..124eb2aa3 100644
--- a/src/ir/table-utils.cpp
+++ b/src/ir/table-utils.cpp
@@ -72,14 +72,11 @@ bool usesExpressions(ElementSegment* curr, Module* module) {
       return entry->is<RefFunc>();
     });
 
-  // If the table has a specialized (non-MVP) type, then the segment must
-  // declare a type that is a subtype of that, so it must use the post-MVP form
-  // of using expressions.
-  bool hasTableOfSpecializedType =
-    curr->table.is() &&
-    module->getTable(curr->table)->type != Type(HeapType::func, Nullable);
+  // If the segment has a specialized (non-MVP) type, then it must use the
+  // post-MVP form of using expressions.
+  bool hasSpecializedType = curr->type != Type(HeapType::func, Nullable);
 
-  return !allElementsRefFunc || hasTableOfSpecializedType;
+  return !allElementsRefFunc || hasSpecializedType;
 }
 
 } // namespace wasm::TableUtils
diff --git a/test/lit/empty-elem.wast b/test/lit/empty-elem.wast
new file mode 100644
index 000000000..0eff01d3c
--- /dev/null
+++ b/test/lit/empty-elem.wast
@@ -0,0 +1,34 @@
+;; NOTE: Assertions have been generated by update_lit_checks.py and should not be edited.
+;; RUN: wasm-opt %s -all --roundtrip -S -o - | filecheck %s
+
+;; Regression test for a bug where empty passive segments were incorrectly
+;; printed and emitted as though they had func type even if they had a different
+;; type, resulting in invalid modules.
+
+(module
+ ;; CHECK:      (type $struct (sub (struct )))
+ (type $struct (sub (struct)))
+
+ ;; CHECK:      (type $array (sub (array (mut (ref null $struct)))))
+ (type $array (sub (array (mut (ref null $struct)))))
+
+ ;; CHECK:      (elem $e (ref null $struct))
+ (elem $e (ref null $struct))
+
+ ;; CHECK:      (func $array-init-elem (type $2)
+ ;; CHECK-NEXT:  (array.init_elem $array $e
+ ;; CHECK-NEXT:   (array.new_fixed $array 0)
+ ;; CHECK-NEXT:   (i32.const 0)
+ ;; CHECK-NEXT:   (i32.const 0)
+ ;; CHECK-NEXT:   (i32.const 0)
+ ;; CHECK-NEXT:  )
+ ;; CHECK-NEXT: )
+ (func $array-init-elem
+  (array.init_elem $array $e
+   (array.new_fixed $array 0)
+   (i32.const 0)
+   (i32.const 0)
+   (i32.const 0)
+  )
+ )
+)
diff --git a/test/multi-table.wast.from-wast b/test/multi-table.wast.from-wast
index 6ff0120f7..426f474e5 100644
--- a/test/multi-table.wast.from-wast
+++ b/test/multi-table.wast.from-wast
@@ -11,7 +11,7 @@
  (elem $1 (table $t2) (i32.const 0) func $f)
  (elem $activeNonZeroOffset (table $t2) (i32.const 1) func $f $g)
  (elem $e3-1 (table $t3) (global.get $g2) funcref (ref.func $f) (ref.null nofunc))
- (elem $e3-2 (table $t3) (i32.const 2) func $f $g)
+ (elem $e3-2 (table $t3) (i32.const 2) (ref null $none_=>_none) (ref.func $f) (ref.func $g))
  (elem $passive-1 func $f $g)
  (elem $passive-2 funcref (ref.func $f) (ref.func $g) (ref.null nofunc))
  (elem $passive-3 (ref null $none_=>_none) (ref.func $f) (ref.func $g) (ref.null nofunc) (global.get $g1))
diff --git a/test/multi-table.wast.fromBinary b/test/multi-table.wast.fromBinary
index 938026af3..c27ec806f 100644
--- a/test/multi-table.wast.fromBinary
+++ b/test/multi-table.wast.fromBinary
@@ -11,7 +11,7 @@
  (elem $1 (table $t2) (i32.const 0) func $f)
  (elem $activeNonZeroOffset (table $t2) (i32.const 1) func $f $g)
  (elem $e3-1 (table $t3) (global.get $g2) funcref (ref.func $f) (ref.null nofunc))
- (elem $e3-2 (table $t3) (i32.const 2) func $f $g)
+ (elem $e3-2 (table $t3) (i32.const 2) (ref null $none_=>_none) (ref.func $f) (ref.func $g))
  (elem $passive-1 func $f $g)
  (elem $passive-2 funcref (ref.func $f) (ref.func $g) (ref.null nofunc))
  (elem $passive-3 (ref null $none_=>_none) (ref.func $f) (ref.func $g) (ref.null nofunc) (global.get $g1))
diff --git a/test/multi-table.wast.fromBinary.noDebugInfo b/test/multi-table.wast.fromBinary.noDebugInfo
index ef7f65167..c2a5ef858 100644
--- a/test/multi-table.wast.fromBinary.noDebugInfo
+++ b/test/multi-table.wast.fromBinary.noDebugInfo
@@ -11,7 +11,7 @@
  (elem $1 (table $0) (i32.const 0) func $0)
  (elem $2 (table $0) (i32.const 1) func $0 $1)
  (elem $3 (table $1) (global.get $global$1) funcref (ref.func $0) (ref.null nofunc))
- (elem $4 (table $1) (i32.const 2) func $0 $1)
+ (elem $4 (table $1) (i32.const 2) (ref null $0) (ref.func $0) (ref.func $1))
  (elem $5 func $0 $1)
  (elem $6 funcref (ref.func $0) (ref.func $1) (ref.null nofunc))
  (elem $7 (ref null $0) (ref.func $0) (ref.func $1) (ref.null nofunc) (global.get $global$0))