diff --git a/source/fuzz/fuzzer_pass_add_loads.cpp b/source/fuzz/fuzzer_pass_add_loads.cpp
index 16d88e3b4..256255bcd 100644
--- a/source/fuzz/fuzzer_pass_add_loads.cpp
+++ b/source/fuzz/fuzzer_pass_add_loads.cpp
@@ -60,7 +60,7 @@ void FuzzerPassAddLoads::Apply() {
                   if (!instruction->result_id() || !instruction->type_id()) {
                     return false;
                   }
-                  switch (instruction->result_id()) {
+                  switch (instruction->opcode()) {
                     case SpvOpConstantNull:
                     case SpvOpUndef:
                       // Do not allow loading from a null or undefined pointer;
diff --git a/source/fuzz/fuzzer_pass_add_stores.cpp b/source/fuzz/fuzzer_pass_add_stores.cpp
index ff660505c..46efc6431 100644
--- a/source/fuzz/fuzzer_pass_add_stores.cpp
+++ b/source/fuzz/fuzzer_pass_add_stores.cpp
@@ -72,7 +72,7 @@ void FuzzerPassAddStores::Apply() {
                     // Read only: cannot store to it.
                     return false;
                   }
-                  switch (instruction->result_id()) {
+                  switch (instruction->opcode()) {
                     case SpvOpConstantNull:
                     case SpvOpUndef:
                       // Do not allow storing to a null or undefined pointer;