diff --git a/ivtest/ivltests/array_index_real_fail.v b/ivtest/ivltests/array_index_real_fail.v
new file mode 100644
index 000000000..763e24ee9
--- /dev/null
+++ b/ivtest/ivltests/array_index_real_fail.v
@@ -0,0 +1,12 @@
+// Check that real expressions can not be used as array indices.
+
+module test;
+
+  reg [1:0] a[1:0];
+  real r;
+
+  initial begin
+    a[r] = 2'b10;
+  end
+
+endmodule
diff --git a/ivtest/regress-vvp.list b/ivtest/regress-vvp.list
index e9c9a1633..13b3a3bf8 100644
--- a/ivtest/regress-vvp.list
+++ b/ivtest/regress-vvp.list
@@ -6,6 +6,7 @@ always4A			vvp_tests/always4A.json
 always4B			vvp_tests/always4B.json
 analog1				vvp_tests/analog1.json
 analog2				vvp_tests/analog2.json
+array_index_real_fail		vvp_tests/array_index_real_fail.json
 array_packed_sysfunct		vvp_tests/array_packed_sysfunct.json
 array_packed_value_list		vvp_tests/array_packed_value_list.json
 array_packed_write_read		vvp_tests/array_packed_write_read.json
diff --git a/ivtest/vvp_tests/array_index_real_fail.json b/ivtest/vvp_tests/array_index_real_fail.json
new file mode 100644
index 000000000..a4b453e0a
--- /dev/null
+++ b/ivtest/vvp_tests/array_index_real_fail.json
@@ -0,0 +1,4 @@
+{
+    "type"   : "CE",
+    "source" : "array_index_real_fail.v"
+}
diff --git a/netmisc.cc b/netmisc.cc
index 9e4162800..66e852820 100644
--- a/netmisc.cc
+++ b/netmisc.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001-2025 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2001-2026 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -509,8 +509,15 @@ void indices_to_expressions(Design*des, NetScope*scope,
 
 	    NetExpr*word_index = elab_and_eval(des, scope, cur->msb, -1, need_const);
 
-	    if (word_index == 0)
+	    if (!word_index) {
 		  flags.invalid = true;
+	    } else if (word_index->expr_type() == IVL_VT_REAL) {
+		  cerr << cur->msb->get_fileline() << ": error: "
+		       << "Array index expression cannot be a real value."
+		       << endl;
+		  des->errors += 1;
+		  flags.invalid = true;
+	    }
 
 	      // Track if we detect any non-constant expressions
 	      // here. This may allow for a special case.