diff --git a/source/diff/diff.cpp b/source/diff/diff.cpp
index 13e1ffa9..3b4c24ed 100644
--- a/source/diff/diff.cpp
+++ b/source/diff/diff.cpp
@@ -307,6 +307,7 @@ class Differ {
                              const opt::Operand& dst_operand);
   bool DoInstructionsMatchFuzzy(const opt::Instruction* src_inst,
                                 const opt::Instruction* dst_inst);
+  bool AreIdenticalUintConstants(uint32_t src_id, uint32_t dst_id);
   bool DoDebugAndAnnotationInstructionsMatch(const opt::Instruction* src_inst,
                                              const opt::Instruction* dst_inst);
   bool AreVariablesMatchable(uint32_t src_id, uint32_t dst_id,
@@ -840,10 +841,8 @@ bool Differ::DoIdsMatchFuzzy(uint32_t src_id, uint32_t dst_id) {
   }
 
   // Int and Uint constants are interchangeable, match them in that case.
-  if (IsConstantUint(src_id_to_, src_id) &&
-      IsConstantUint(dst_id_to_, dst_id)) {
-    return GetConstantUint(src_id_to_, src_id) ==
-           GetConstantUint(dst_id_to_, dst_id);
+  if (AreIdenticalUintConstants(src_id, dst_id)) {
+    return true;
   }
 
   return false;
@@ -911,6 +910,13 @@ bool Differ::DoInstructionsMatchFuzzy(const opt::Instruction* src_inst,
   return match;
 }
 
+bool Differ::AreIdenticalUintConstants(uint32_t src_id, uint32_t dst_id) {
+  return IsConstantUint(src_id_to_, src_id) &&
+         IsConstantUint(dst_id_to_, dst_id) &&
+         GetConstantUint(src_id_to_, src_id) ==
+             GetConstantUint(dst_id_to_, dst_id);
+}
+
 bool Differ::DoDebugAndAnnotationInstructionsMatch(
     const opt::Instruction* src_inst, const opt::Instruction* dst_inst) {
   if (src_inst->opcode() != dst_inst->opcode()) {
@@ -2001,9 +2007,14 @@ void Differ::MatchTypeIds() {
             return false;
           }
 
-          return GetConstantUint(src_id_to_,
-                                 src_inst->GetInOperand(1).AsId()) ==
-                 GetConstantUint(dst_id_to_, dst_inst->GetInOperand(1).AsId());
+          if (AreIdenticalUintConstants(src_inst->GetInOperand(1).AsId(),
+                                        dst_inst->GetInOperand(1).AsId())) {
+            return true;
+          }
+
+          // If size is not OpConstant, expect the ids to match exactly (for
+          // example if a spec contant is used).
+          return DoOperandsMatch(src_inst, dst_inst, 1, 1);
 
         case SpvOpTypeStruct:
           return MatchOpTypeStruct(src_inst, dst_inst, flexibility);
diff --git a/test/diff/diff_files/constant_array_size_autogen.cpp b/test/diff/diff_files/constant_array_size_autogen.cpp
new file mode 100644
index 00000000..16975ff4
--- /dev/null
+++ b/test/diff/diff_files/constant_array_size_autogen.cpp
@@ -0,0 +1,306 @@
+// GENERATED FILE - DO NOT EDIT.
+// Generated by generate_tests.py
+//
+// Copyright (c) 2022 Google LLC.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "../diff_test_utils.h"
+
+#include "gtest/gtest.h"
+
+namespace spvtools {
+namespace diff {
+namespace {
+
+// Tests that identical integer constants are matched when used as array size,
+// regardless of int or uint.
+constexpr char kSrc[] = R"(; SPIR-V
+; Version: 1.0
+; Generator: Google ANGLE Shader Compiler; 0
+; Bound: 27
+; Schema: 0
+OpCapability Shader
+OpMemoryModel Logical GLSL450
+OpEntryPoint Vertex %22 "main" %4 %19
+OpSource GLSL 450
+OpName %4 "_ua_position"
+OpName %17 "gl_PerVertex"
+OpMemberName %17 0 "gl_Position"
+OpMemberName %17 1 "gl_PointSize"
+OpMemberName %17 2 "gl_ClipDistance"
+OpMemberName %17 3 "gl_CullDistance"
+OpName %19 ""
+OpName %22 "main"
+OpDecorate %4 Location 0
+OpMemberDecorate %17 1 RelaxedPrecision
+OpMemberDecorate %17 0 BuiltIn Position
+OpMemberDecorate %17 1 BuiltIn PointSize
+OpMemberDecorate %17 2 BuiltIn ClipDistance
+OpMemberDecorate %17 3 BuiltIn CullDistance
+OpDecorate %17 Block
+%1 = OpTypeFloat 32
+%2 = OpTypeVector %1 4
+%5 = OpTypeInt 32 0
+%8 = OpTypeVector %5 4
+%15 = OpConstant %5 8
+%16 = OpTypeArray %1 %15
+%17 = OpTypeStruct %2 %1 %16 %16
+%20 = OpTypeVoid
+%25 = OpConstant %5 0
+%3 = OpTypePointer Input %2
+%13 = OpTypePointer Output %2
+%18 = OpTypePointer Output %17
+%21 = OpTypeFunction %20
+%4 = OpVariable %3 Input
+%19 = OpVariable %18 Output
+%22 = OpFunction %20 None %21
+%23 = OpLabel
+%24 = OpLoad %2 %4
+%26 = OpAccessChain %13 %19 %25
+OpStore %26 %24
+OpReturn
+OpFunctionEnd)";
+constexpr char kDst[] = R"(; SPIR-V
+; Version: 1.0
+; Generator: Google ANGLE Shader Compiler; 0
+; Bound: 27
+; Schema: 0
+OpCapability Shader
+OpMemoryModel Logical GLSL450
+OpEntryPoint Vertex %22 "main" %4 %19
+OpSource GLSL 450
+OpName %4 "_ua_position"
+OpName %17 "gl_PerVertex"
+OpMemberName %17 0 "gl_Position"
+OpMemberName %17 1 "gl_PointSize"
+OpMemberName %17 2 "gl_ClipDistance"
+OpMemberName %17 3 "gl_CullDistance"
+OpName %19 ""
+OpName %22 "main"
+OpDecorate %4 Location 0
+OpMemberDecorate %17 1 RelaxedPrecision
+OpMemberDecorate %17 0 BuiltIn Position
+OpMemberDecorate %17 1 BuiltIn PointSize
+OpMemberDecorate %17 2 BuiltIn ClipDistance
+OpMemberDecorate %17 3 BuiltIn CullDistance
+OpDecorate %17 Block
+%1 = OpTypeFloat 32
+%2 = OpTypeVector %1 4
+%5 = OpTypeInt 32 0
+%6 = OpTypeInt 32 1
+%8 = OpTypeVector %5 4
+%15 = OpConstant %6 8
+%16 = OpTypeArray %1 %15
+%17 = OpTypeStruct %2 %1 %16 %16
+%20 = OpTypeVoid
+%25 = OpConstant %5 0
+%3 = OpTypePointer Input %2
+%13 = OpTypePointer Output %2
+%18 = OpTypePointer Output %17
+%21 = OpTypeFunction %20
+%4 = OpVariable %3 Input
+%19 = OpVariable %18 Output
+%22 = OpFunction %20 None %21
+%23 = OpLabel
+%24 = OpLoad %2 %4
+%26 = OpAccessChain %13 %19 %25
+OpStore %26 %24
+OpReturn
+OpFunctionEnd
+)";
+
+TEST(DiffTest, ConstantArraySize) {
+  constexpr char kDiff[] = R"( ; SPIR-V
+ ; Version: 1.6
+ ; Generator: Khronos SPIR-V Tools Assembler; 0
+-; Bound: 27
++; Bound: 34
+ ; Schema: 0
+ OpCapability Shader
+ OpMemoryModel Logical GLSL450
+ OpEntryPoint Vertex %22 "main" %4 %19
+ OpSource GLSL 450
+ OpName %4 "_ua_position"
+ OpName %17 "gl_PerVertex"
+ OpMemberName %17 0 "gl_Position"
+ OpMemberName %17 1 "gl_PointSize"
+ OpMemberName %17 2 "gl_ClipDistance"
+ OpMemberName %17 3 "gl_CullDistance"
+ OpName %19 ""
+ OpName %22 "main"
+ OpDecorate %4 Location 0
+ OpMemberDecorate %17 1 RelaxedPrecision
+ OpMemberDecorate %17 0 BuiltIn Position
+ OpMemberDecorate %17 1 BuiltIn PointSize
+ OpMemberDecorate %17 2 BuiltIn ClipDistance
+ OpMemberDecorate %17 3 BuiltIn CullDistance
+ OpDecorate %17 Block
+ %1 = OpTypeFloat 32
+ %2 = OpTypeVector %1 4
+ %5 = OpTypeInt 32 0
++%27 = OpTypeInt 32 1
+ %8 = OpTypeVector %5 4
+-%15 = OpConstant %5 8
++%15 = OpConstant %27 8
+ %16 = OpTypeArray %1 %15
+ %17 = OpTypeStruct %2 %1 %16 %16
+ %20 = OpTypeVoid
+ %25 = OpConstant %5 0
+ %3 = OpTypePointer Input %2
+ %13 = OpTypePointer Output %2
+ %18 = OpTypePointer Output %17
+ %21 = OpTypeFunction %20
+ %4 = OpVariable %3 Input
+ %19 = OpVariable %18 Output
+ %22 = OpFunction %20 None %21
+ %23 = OpLabel
+ %24 = OpLoad %2 %4
+ %26 = OpAccessChain %13 %19 %25
+ OpStore %26 %24
+ OpReturn
+ OpFunctionEnd
+)";
+  Options options;
+  DoStringDiffTest(kSrc, kDst, kDiff, options);
+}
+
+TEST(DiffTest, ConstantArraySizeNoDebug) {
+  constexpr char kSrcNoDebug[] = R"(; SPIR-V
+; Version: 1.0
+; Generator: Google ANGLE Shader Compiler; 0
+; Bound: 27
+; Schema: 0
+OpCapability Shader
+OpMemoryModel Logical GLSL450
+OpEntryPoint Vertex %22 "main" %4 %19
+OpSource GLSL 450
+OpDecorate %4 Location 0
+OpMemberDecorate %17 1 RelaxedPrecision
+OpMemberDecorate %17 0 BuiltIn Position
+OpMemberDecorate %17 1 BuiltIn PointSize
+OpMemberDecorate %17 2 BuiltIn ClipDistance
+OpMemberDecorate %17 3 BuiltIn CullDistance
+OpDecorate %17 Block
+%1 = OpTypeFloat 32
+%2 = OpTypeVector %1 4
+%5 = OpTypeInt 32 0
+%8 = OpTypeVector %5 4
+%15 = OpConstant %5 8
+%16 = OpTypeArray %1 %15
+%17 = OpTypeStruct %2 %1 %16 %16
+%20 = OpTypeVoid
+%25 = OpConstant %5 0
+%3 = OpTypePointer Input %2
+%13 = OpTypePointer Output %2
+%18 = OpTypePointer Output %17
+%21 = OpTypeFunction %20
+%4 = OpVariable %3 Input
+%19 = OpVariable %18 Output
+%22 = OpFunction %20 None %21
+%23 = OpLabel
+%24 = OpLoad %2 %4
+%26 = OpAccessChain %13 %19 %25
+OpStore %26 %24
+OpReturn
+OpFunctionEnd
+)";
+  constexpr char kDstNoDebug[] = R"(; SPIR-V
+; Version: 1.0
+; Generator: Google ANGLE Shader Compiler; 0
+; Bound: 27
+; Schema: 0
+OpCapability Shader
+OpMemoryModel Logical GLSL450
+OpEntryPoint Vertex %22 "main" %4 %19
+OpSource GLSL 450
+OpDecorate %4 Location 0
+OpMemberDecorate %17 1 RelaxedPrecision
+OpMemberDecorate %17 0 BuiltIn Position
+OpMemberDecorate %17 1 BuiltIn PointSize
+OpMemberDecorate %17 2 BuiltIn ClipDistance
+OpMemberDecorate %17 3 BuiltIn CullDistance
+OpDecorate %17 Block
+%1 = OpTypeFloat 32
+%2 = OpTypeVector %1 4
+%5 = OpTypeInt 32 0
+%6 = OpTypeInt 32 1
+%8 = OpTypeVector %5 4
+%15 = OpConstant %6 8
+%16 = OpTypeArray %1 %15
+%17 = OpTypeStruct %2 %1 %16 %16
+%20 = OpTypeVoid
+%25 = OpConstant %5 0
+%3 = OpTypePointer Input %2
+%13 = OpTypePointer Output %2
+%18 = OpTypePointer Output %17
+%21 = OpTypeFunction %20
+%4 = OpVariable %3 Input
+%19 = OpVariable %18 Output
+%22 = OpFunction %20 None %21
+%23 = OpLabel
+%24 = OpLoad %2 %4
+%26 = OpAccessChain %13 %19 %25
+OpStore %26 %24
+OpReturn
+OpFunctionEnd
+)";
+  constexpr char kDiff[] = R"( ; SPIR-V
+ ; Version: 1.6
+ ; Generator: Khronos SPIR-V Tools Assembler; 0
+-; Bound: 27
++; Bound: 34
+ ; Schema: 0
+ OpCapability Shader
+ OpMemoryModel Logical GLSL450
+ OpEntryPoint Vertex %22 "main" %4 %19
+ OpSource GLSL 450
+ OpDecorate %4 Location 0
+ OpMemberDecorate %17 1 RelaxedPrecision
+ OpMemberDecorate %17 0 BuiltIn Position
+ OpMemberDecorate %17 1 BuiltIn PointSize
+ OpMemberDecorate %17 2 BuiltIn ClipDistance
+ OpMemberDecorate %17 3 BuiltIn CullDistance
+ OpDecorate %17 Block
+ %1 = OpTypeFloat 32
+ %2 = OpTypeVector %1 4
+ %5 = OpTypeInt 32 0
++%27 = OpTypeInt 32 1
+ %8 = OpTypeVector %5 4
+-%15 = OpConstant %5 8
++%15 = OpConstant %27 8
+ %16 = OpTypeArray %1 %15
+ %17 = OpTypeStruct %2 %1 %16 %16
+ %20 = OpTypeVoid
+ %25 = OpConstant %5 0
+ %3 = OpTypePointer Input %2
+ %13 = OpTypePointer Output %2
+ %18 = OpTypePointer Output %17
+ %21 = OpTypeFunction %20
+ %4 = OpVariable %3 Input
+ %19 = OpVariable %18 Output
+ %22 = OpFunction %20 None %21
+ %23 = OpLabel
+ %24 = OpLoad %2 %4
+ %26 = OpAccessChain %13 %19 %25
+ OpStore %26 %24
+ OpReturn
+ OpFunctionEnd
+)";
+  Options options;
+  DoStringDiffTest(kSrcNoDebug, kDstNoDebug, kDiff, options);
+}
+
+}  // namespace
+}  // namespace diff
+}  // namespace spvtools
diff --git a/test/diff/diff_files/constant_array_size_dst.spvasm b/test/diff/diff_files/constant_array_size_dst.spvasm
new file mode 100644
index 00000000..a432b612
--- /dev/null
+++ b/test/diff/diff_files/constant_array_size_dst.spvasm
@@ -0,0 +1,47 @@
+; SPIR-V
+; Version: 1.0
+; Generator: Google ANGLE Shader Compiler; 0
+; Bound: 27
+; Schema: 0
+OpCapability Shader
+OpMemoryModel Logical GLSL450
+OpEntryPoint Vertex %22 "main" %4 %19
+OpSource GLSL 450
+OpName %4 "_ua_position"
+OpName %17 "gl_PerVertex"
+OpMemberName %17 0 "gl_Position"
+OpMemberName %17 1 "gl_PointSize"
+OpMemberName %17 2 "gl_ClipDistance"
+OpMemberName %17 3 "gl_CullDistance"
+OpName %19 ""
+OpName %22 "main"
+OpDecorate %4 Location 0
+OpMemberDecorate %17 1 RelaxedPrecision
+OpMemberDecorate %17 0 BuiltIn Position
+OpMemberDecorate %17 1 BuiltIn PointSize
+OpMemberDecorate %17 2 BuiltIn ClipDistance
+OpMemberDecorate %17 3 BuiltIn CullDistance
+OpDecorate %17 Block
+%1 = OpTypeFloat 32
+%2 = OpTypeVector %1 4
+%5 = OpTypeInt 32 0
+%6 = OpTypeInt 32 1
+%8 = OpTypeVector %5 4
+%15 = OpConstant %6 8
+%16 = OpTypeArray %1 %15
+%17 = OpTypeStruct %2 %1 %16 %16
+%20 = OpTypeVoid
+%25 = OpConstant %5 0
+%3 = OpTypePointer Input %2
+%13 = OpTypePointer Output %2
+%18 = OpTypePointer Output %17
+%21 = OpTypeFunction %20
+%4 = OpVariable %3 Input
+%19 = OpVariable %18 Output
+%22 = OpFunction %20 None %21
+%23 = OpLabel
+%24 = OpLoad %2 %4
+%26 = OpAccessChain %13 %19 %25
+OpStore %26 %24
+OpReturn
+OpFunctionEnd
diff --git a/test/diff/diff_files/constant_array_size_src.spvasm b/test/diff/diff_files/constant_array_size_src.spvasm
new file mode 100644
index 00000000..4e1ba646
--- /dev/null
+++ b/test/diff/diff_files/constant_array_size_src.spvasm
@@ -0,0 +1,48 @@
+;; Tests that identical integer constants are matched when used as array size,
+;; regardless of int or uint.
+; SPIR-V
+; Version: 1.0
+; Generator: Google ANGLE Shader Compiler; 0
+; Bound: 27
+; Schema: 0
+OpCapability Shader
+OpMemoryModel Logical GLSL450
+OpEntryPoint Vertex %22 "main" %4 %19
+OpSource GLSL 450
+OpName %4 "_ua_position"
+OpName %17 "gl_PerVertex"
+OpMemberName %17 0 "gl_Position"
+OpMemberName %17 1 "gl_PointSize"
+OpMemberName %17 2 "gl_ClipDistance"
+OpMemberName %17 3 "gl_CullDistance"
+OpName %19 ""
+OpName %22 "main"
+OpDecorate %4 Location 0
+OpMemberDecorate %17 1 RelaxedPrecision
+OpMemberDecorate %17 0 BuiltIn Position
+OpMemberDecorate %17 1 BuiltIn PointSize
+OpMemberDecorate %17 2 BuiltIn ClipDistance
+OpMemberDecorate %17 3 BuiltIn CullDistance
+OpDecorate %17 Block
+%1 = OpTypeFloat 32
+%2 = OpTypeVector %1 4
+%5 = OpTypeInt 32 0
+%8 = OpTypeVector %5 4
+%15 = OpConstant %5 8
+%16 = OpTypeArray %1 %15
+%17 = OpTypeStruct %2 %1 %16 %16
+%20 = OpTypeVoid
+%25 = OpConstant %5 0
+%3 = OpTypePointer Input %2
+%13 = OpTypePointer Output %2
+%18 = OpTypePointer Output %17
+%21 = OpTypeFunction %20
+%4 = OpVariable %3 Input
+%19 = OpVariable %18 Output
+%22 = OpFunction %20 None %21
+%23 = OpLabel
+%24 = OpLoad %2 %4
+%26 = OpAccessChain %13 %19 %25
+OpStore %26 %24
+OpReturn
+OpFunctionEnd
diff --git a/test/diff/diff_files/diff_test_files_autogen.cmake b/test/diff/diff_files/diff_test_files_autogen.cmake
index 9c72448a..7887f106 100644
--- a/test/diff/diff_files/diff_test_files_autogen.cmake
+++ b/test/diff/diff_files/diff_test_files_autogen.cmake
@@ -19,6 +19,7 @@ list(APPEND DIFF_TEST_FILES
 "diff_files/OpExtInst_in_dst_only_autogen.cpp"
 "diff_files/OpExtInst_in_src_only_autogen.cpp"
 "diff_files/basic_autogen.cpp"
+"diff_files/constant_array_size_autogen.cpp"
 "diff_files/different_decorations_fragment_autogen.cpp"
 "diff_files/different_decorations_vertex_autogen.cpp"
 "diff_files/extra_if_block_autogen.cpp"
@@ -31,5 +32,6 @@ list(APPEND DIFF_TEST_FILES
 "diff_files/reordered_if_blocks_autogen.cpp"
 "diff_files/reordered_switch_blocks_autogen.cpp"
 "diff_files/small_functions_small_diffs_autogen.cpp"
+"diff_files/spec_constant_array_size_autogen.cpp"
 "diff_files/unrelated_shaders_autogen.cpp"
 )
diff --git a/test/diff/diff_files/spec_constant_array_size_autogen.cpp b/test/diff/diff_files/spec_constant_array_size_autogen.cpp
new file mode 100644
index 00000000..1962d27e
--- /dev/null
+++ b/test/diff/diff_files/spec_constant_array_size_autogen.cpp
@@ -0,0 +1,310 @@
+// GENERATED FILE - DO NOT EDIT.
+// Generated by generate_tests.py
+//
+// Copyright (c) 2022 Google LLC.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "../diff_test_utils.h"
+
+#include "gtest/gtest.h"
+
+namespace spvtools {
+namespace diff {
+namespace {
+
+// Tests that identical specialization constants are not matched with constants
+// when used as array size.
+constexpr char kSrc[] = R"(; SPIR-V
+; Version: 1.0
+; Generator: Google ANGLE Shader Compiler; 0
+; Bound: 27
+; Schema: 0
+OpCapability Shader
+OpMemoryModel Logical GLSL450
+OpEntryPoint Vertex %22 "main" %4 %19
+OpSource GLSL 450
+OpName %4 "_ua_position"
+OpName %17 "gl_PerVertex"
+OpMemberName %17 0 "gl_Position"
+OpMemberName %17 1 "gl_PointSize"
+OpMemberName %17 2 "gl_ClipDistance"
+OpMemberName %17 3 "gl_CullDistance"
+OpName %19 ""
+OpName %22 "main"
+OpDecorate %4 Location 0
+OpMemberDecorate %17 1 RelaxedPrecision
+OpMemberDecorate %17 0 BuiltIn Position
+OpMemberDecorate %17 1 BuiltIn PointSize
+OpMemberDecorate %17 2 BuiltIn ClipDistance
+OpMemberDecorate %17 3 BuiltIn CullDistance
+OpDecorate %17 Block
+%1 = OpTypeFloat 32
+%2 = OpTypeVector %1 4
+%5 = OpTypeInt 32 0
+%8 = OpTypeVector %5 4
+%15 = OpConstant %5 8
+%16 = OpTypeArray %1 %15
+%17 = OpTypeStruct %2 %1 %16 %16
+%20 = OpTypeVoid
+%25 = OpConstant %5 0
+%3 = OpTypePointer Input %2
+%13 = OpTypePointer Output %2
+%18 = OpTypePointer Output %17
+%21 = OpTypeFunction %20
+%4 = OpVariable %3 Input
+%19 = OpVariable %18 Output
+%22 = OpFunction %20 None %21
+%23 = OpLabel
+%24 = OpLoad %2 %4
+%26 = OpAccessChain %13 %19 %25
+OpStore %26 %24
+OpReturn
+OpFunctionEnd)";
+constexpr char kDst[] = R"(; SPIR-V
+; Version: 1.0
+; Generator: Google ANGLE Shader Compiler; 0
+; Bound: 27
+; Schema: 0
+OpCapability Shader
+OpMemoryModel Logical GLSL450
+OpEntryPoint Vertex %22 "main" %4 %19
+OpSource GLSL 450
+OpName %4 "_ua_position"
+OpName %17 "gl_PerVertex"
+OpMemberName %17 0 "gl_Position"
+OpMemberName %17 1 "gl_PointSize"
+OpMemberName %17 2 "gl_ClipDistance"
+OpMemberName %17 3 "gl_CullDistance"
+OpName %19 ""
+OpName %22 "main"
+OpDecorate %4 Location 0
+OpDecorate %15 SpecId 4
+OpMemberDecorate %17 1 RelaxedPrecision
+OpMemberDecorate %17 0 BuiltIn Position
+OpMemberDecorate %17 1 BuiltIn PointSize
+OpMemberDecorate %17 2 BuiltIn ClipDistance
+OpMemberDecorate %17 3 BuiltIn CullDistance
+OpDecorate %17 Block
+%1 = OpTypeFloat 32
+%2 = OpTypeVector %1 4
+%5 = OpTypeInt 32 0
+%8 = OpTypeVector %5 4
+%15 = OpSpecConstant %5 8
+%16 = OpTypeArray %1 %15
+%17 = OpTypeStruct %2 %1 %16 %16
+%20 = OpTypeVoid
+%25 = OpConstant %5 0
+%3 = OpTypePointer Input %2
+%13 = OpTypePointer Output %2
+%18 = OpTypePointer Output %17
+%21 = OpTypeFunction %20
+%4 = OpVariable %3 Input
+%19 = OpVariable %18 Output
+%22 = OpFunction %20 None %21
+%23 = OpLabel
+%24 = OpLoad %2 %4
+%26 = OpAccessChain %13 %19 %25
+OpStore %26 %24
+OpReturn
+OpFunctionEnd
+)";
+
+TEST(DiffTest, SpecConstantArraySize) {
+  constexpr char kDiff[] = R"( ; SPIR-V
+ ; Version: 1.6
+ ; Generator: Khronos SPIR-V Tools Assembler; 0
+-; Bound: 27
++; Bound: 36
+ ; Schema: 0
+ OpCapability Shader
+ OpMemoryModel Logical GLSL450
+ OpEntryPoint Vertex %22 "main" %4 %19
+ OpSource GLSL 450
+ OpName %4 "_ua_position"
+ OpName %17 "gl_PerVertex"
+ OpMemberName %17 0 "gl_Position"
+ OpMemberName %17 1 "gl_PointSize"
+ OpMemberName %17 2 "gl_ClipDistance"
+ OpMemberName %17 3 "gl_CullDistance"
+ OpName %19 ""
+ OpName %22 "main"
+ OpDecorate %4 Location 0
++OpDecorate %34 SpecId 4
+ OpMemberDecorate %17 1 RelaxedPrecision
+ OpMemberDecorate %17 0 BuiltIn Position
+ OpMemberDecorate %17 1 BuiltIn PointSize
+ OpMemberDecorate %17 2 BuiltIn ClipDistance
+ OpMemberDecorate %17 3 BuiltIn CullDistance
+ OpDecorate %17 Block
+ %1 = OpTypeFloat 32
+ %2 = OpTypeVector %1 4
+ %5 = OpTypeInt 32 0
+ %8 = OpTypeVector %5 4
+-%15 = OpConstant %5 8
+-%16 = OpTypeArray %1 %15
++%34 = OpSpecConstant %5 8
++%35 = OpTypeArray %1 %34
+-%17 = OpTypeStruct %2 %1 %16 %16
++%17 = OpTypeStruct %2 %1 %35 %35
+ %20 = OpTypeVoid
+ %25 = OpConstant %5 0
+ %3 = OpTypePointer Input %2
+ %13 = OpTypePointer Output %2
+ %18 = OpTypePointer Output %17
+ %21 = OpTypeFunction %20
+ %4 = OpVariable %3 Input
+ %19 = OpVariable %18 Output
+ %22 = OpFunction %20 None %21
+ %23 = OpLabel
+ %24 = OpLoad %2 %4
+ %26 = OpAccessChain %13 %19 %25
+ OpStore %26 %24
+ OpReturn
+ OpFunctionEnd
+)";
+  Options options;
+  DoStringDiffTest(kSrc, kDst, kDiff, options);
+}
+
+TEST(DiffTest, SpecConstantArraySizeNoDebug) {
+  constexpr char kSrcNoDebug[] = R"(; SPIR-V
+; Version: 1.0
+; Generator: Google ANGLE Shader Compiler; 0
+; Bound: 27
+; Schema: 0
+OpCapability Shader
+OpMemoryModel Logical GLSL450
+OpEntryPoint Vertex %22 "main" %4 %19
+OpSource GLSL 450
+OpDecorate %4 Location 0
+OpMemberDecorate %17 1 RelaxedPrecision
+OpMemberDecorate %17 0 BuiltIn Position
+OpMemberDecorate %17 1 BuiltIn PointSize
+OpMemberDecorate %17 2 BuiltIn ClipDistance
+OpMemberDecorate %17 3 BuiltIn CullDistance
+OpDecorate %17 Block
+%1 = OpTypeFloat 32
+%2 = OpTypeVector %1 4
+%5 = OpTypeInt 32 0
+%8 = OpTypeVector %5 4
+%15 = OpConstant %5 8
+%16 = OpTypeArray %1 %15
+%17 = OpTypeStruct %2 %1 %16 %16
+%20 = OpTypeVoid
+%25 = OpConstant %5 0
+%3 = OpTypePointer Input %2
+%13 = OpTypePointer Output %2
+%18 = OpTypePointer Output %17
+%21 = OpTypeFunction %20
+%4 = OpVariable %3 Input
+%19 = OpVariable %18 Output
+%22 = OpFunction %20 None %21
+%23 = OpLabel
+%24 = OpLoad %2 %4
+%26 = OpAccessChain %13 %19 %25
+OpStore %26 %24
+OpReturn
+OpFunctionEnd
+)";
+  constexpr char kDstNoDebug[] = R"(; SPIR-V
+; Version: 1.0
+; Generator: Google ANGLE Shader Compiler; 0
+; Bound: 27
+; Schema: 0
+OpCapability Shader
+OpMemoryModel Logical GLSL450
+OpEntryPoint Vertex %22 "main" %4 %19
+OpSource GLSL 450
+OpDecorate %4 Location 0
+OpDecorate %15 SpecId 4
+OpMemberDecorate %17 1 RelaxedPrecision
+OpMemberDecorate %17 0 BuiltIn Position
+OpMemberDecorate %17 1 BuiltIn PointSize
+OpMemberDecorate %17 2 BuiltIn ClipDistance
+OpMemberDecorate %17 3 BuiltIn CullDistance
+OpDecorate %17 Block
+%1 = OpTypeFloat 32
+%2 = OpTypeVector %1 4
+%5 = OpTypeInt 32 0
+%8 = OpTypeVector %5 4
+%15 = OpSpecConstant %5 8
+%16 = OpTypeArray %1 %15
+%17 = OpTypeStruct %2 %1 %16 %16
+%20 = OpTypeVoid
+%25 = OpConstant %5 0
+%3 = OpTypePointer Input %2
+%13 = OpTypePointer Output %2
+%18 = OpTypePointer Output %17
+%21 = OpTypeFunction %20
+%4 = OpVariable %3 Input
+%19 = OpVariable %18 Output
+%22 = OpFunction %20 None %21
+%23 = OpLabel
+%24 = OpLoad %2 %4
+%26 = OpAccessChain %13 %19 %25
+OpStore %26 %24
+OpReturn
+OpFunctionEnd
+)";
+  constexpr char kDiff[] = R"( ; SPIR-V
+ ; Version: 1.6
+ ; Generator: Khronos SPIR-V Tools Assembler; 0
+-; Bound: 27
++; Bound: 36
+ ; Schema: 0
+ OpCapability Shader
+ OpMemoryModel Logical GLSL450
+ OpEntryPoint Vertex %22 "main" %4 %19
+ OpSource GLSL 450
+ OpDecorate %4 Location 0
++OpDecorate %34 SpecId 4
+ OpMemberDecorate %17 1 RelaxedPrecision
+ OpMemberDecorate %17 0 BuiltIn Position
+ OpMemberDecorate %17 1 BuiltIn PointSize
+ OpMemberDecorate %17 2 BuiltIn ClipDistance
+ OpMemberDecorate %17 3 BuiltIn CullDistance
+ OpDecorate %17 Block
+ %1 = OpTypeFloat 32
+ %2 = OpTypeVector %1 4
+ %5 = OpTypeInt 32 0
+ %8 = OpTypeVector %5 4
+-%15 = OpConstant %5 8
+-%16 = OpTypeArray %1 %15
++%34 = OpSpecConstant %5 8
++%35 = OpTypeArray %1 %34
+-%17 = OpTypeStruct %2 %1 %16 %16
++%17 = OpTypeStruct %2 %1 %35 %35
+ %20 = OpTypeVoid
+ %25 = OpConstant %5 0
+ %3 = OpTypePointer Input %2
+ %13 = OpTypePointer Output %2
+ %18 = OpTypePointer Output %17
+ %21 = OpTypeFunction %20
+ %4 = OpVariable %3 Input
+ %19 = OpVariable %18 Output
+ %22 = OpFunction %20 None %21
+ %23 = OpLabel
+ %24 = OpLoad %2 %4
+ %26 = OpAccessChain %13 %19 %25
+ OpStore %26 %24
+ OpReturn
+ OpFunctionEnd
+)";
+  Options options;
+  DoStringDiffTest(kSrcNoDebug, kDstNoDebug, kDiff, options);
+}
+
+}  // namespace
+}  // namespace diff
+}  // namespace spvtools
diff --git a/test/diff/diff_files/spec_constant_array_size_dst.spvasm b/test/diff/diff_files/spec_constant_array_size_dst.spvasm
new file mode 100644
index 00000000..7cedf083
--- /dev/null
+++ b/test/diff/diff_files/spec_constant_array_size_dst.spvasm
@@ -0,0 +1,47 @@
+; SPIR-V
+; Version: 1.0
+; Generator: Google ANGLE Shader Compiler; 0
+; Bound: 27
+; Schema: 0
+OpCapability Shader
+OpMemoryModel Logical GLSL450
+OpEntryPoint Vertex %22 "main" %4 %19
+OpSource GLSL 450
+OpName %4 "_ua_position"
+OpName %17 "gl_PerVertex"
+OpMemberName %17 0 "gl_Position"
+OpMemberName %17 1 "gl_PointSize"
+OpMemberName %17 2 "gl_ClipDistance"
+OpMemberName %17 3 "gl_CullDistance"
+OpName %19 ""
+OpName %22 "main"
+OpDecorate %4 Location 0
+OpDecorate %15 SpecId 4
+OpMemberDecorate %17 1 RelaxedPrecision
+OpMemberDecorate %17 0 BuiltIn Position
+OpMemberDecorate %17 1 BuiltIn PointSize
+OpMemberDecorate %17 2 BuiltIn ClipDistance
+OpMemberDecorate %17 3 BuiltIn CullDistance
+OpDecorate %17 Block
+%1 = OpTypeFloat 32
+%2 = OpTypeVector %1 4
+%5 = OpTypeInt 32 0
+%8 = OpTypeVector %5 4
+%15 = OpSpecConstant %5 8
+%16 = OpTypeArray %1 %15
+%17 = OpTypeStruct %2 %1 %16 %16
+%20 = OpTypeVoid
+%25 = OpConstant %5 0
+%3 = OpTypePointer Input %2
+%13 = OpTypePointer Output %2
+%18 = OpTypePointer Output %17
+%21 = OpTypeFunction %20
+%4 = OpVariable %3 Input
+%19 = OpVariable %18 Output
+%22 = OpFunction %20 None %21
+%23 = OpLabel
+%24 = OpLoad %2 %4
+%26 = OpAccessChain %13 %19 %25
+OpStore %26 %24
+OpReturn
+OpFunctionEnd
diff --git a/test/diff/diff_files/spec_constant_array_size_src.spvasm b/test/diff/diff_files/spec_constant_array_size_src.spvasm
new file mode 100644
index 00000000..e17e04ac
--- /dev/null
+++ b/test/diff/diff_files/spec_constant_array_size_src.spvasm
@@ -0,0 +1,48 @@
+;; Tests that identical specialization constants are not matched with constants
+;; when used as array size.
+; SPIR-V
+; Version: 1.0
+; Generator: Google ANGLE Shader Compiler; 0
+; Bound: 27
+; Schema: 0
+OpCapability Shader
+OpMemoryModel Logical GLSL450
+OpEntryPoint Vertex %22 "main" %4 %19
+OpSource GLSL 450
+OpName %4 "_ua_position"
+OpName %17 "gl_PerVertex"
+OpMemberName %17 0 "gl_Position"
+OpMemberName %17 1 "gl_PointSize"
+OpMemberName %17 2 "gl_ClipDistance"
+OpMemberName %17 3 "gl_CullDistance"
+OpName %19 ""
+OpName %22 "main"
+OpDecorate %4 Location 0
+OpMemberDecorate %17 1 RelaxedPrecision
+OpMemberDecorate %17 0 BuiltIn Position
+OpMemberDecorate %17 1 BuiltIn PointSize
+OpMemberDecorate %17 2 BuiltIn ClipDistance
+OpMemberDecorate %17 3 BuiltIn CullDistance
+OpDecorate %17 Block
+%1 = OpTypeFloat 32
+%2 = OpTypeVector %1 4
+%5 = OpTypeInt 32 0
+%8 = OpTypeVector %5 4
+%15 = OpConstant %5 8
+%16 = OpTypeArray %1 %15
+%17 = OpTypeStruct %2 %1 %16 %16
+%20 = OpTypeVoid
+%25 = OpConstant %5 0
+%3 = OpTypePointer Input %2
+%13 = OpTypePointer Output %2
+%18 = OpTypePointer Output %17
+%21 = OpTypeFunction %20
+%4 = OpVariable %3 Input
+%19 = OpVariable %18 Output
+%22 = OpFunction %20 None %21
+%23 = OpLabel
+%24 = OpLoad %2 %4
+%26 = OpAccessChain %13 %19 %25
+OpStore %26 %24
+OpReturn
+OpFunctionEnd