diff --git a/source/val/validate_adjacency.cpp b/source/val/validate_adjacency.cpp
index ae2eff3f8..47bfe46e4 100644
--- a/source/val/validate_adjacency.cpp
+++ b/source/val/validate_adjacency.cpp
@@ -28,28 +28,34 @@ namespace spvtools {
 namespace val {
 
 enum {
+  // Status right after meeting OpFunction.
   IN_NEW_FUNCTION,
+  // Status right after meeting the entry block.
   IN_ENTRY_BLOCK,
+  // Status right after meeting non-entry blocks.
   PHI_VALID,
-  PHI_INVALID,
+  // Status right after meeting non-OpVariable instructions in the entry block
+  // or non-OpPhi instructions in non-entry blocks, except OpLine.
+  PHI_AND_VAR_INVALID,
 };
 
 spv_result_t ValidateAdjacency(ValidationState_t& _) {
   const auto& instructions = _.ordered_instructions();
-  int phi_check = PHI_INVALID;
+  int adjacency_status = PHI_AND_VAR_INVALID;
 
   for (size_t i = 0; i < instructions.size(); ++i) {
     const auto& inst = instructions[i];
     switch (inst.opcode()) {
       case SpvOpFunction:
       case SpvOpFunctionParameter:
-        phi_check = IN_NEW_FUNCTION;
+        adjacency_status = IN_NEW_FUNCTION;
         break;
       case SpvOpLabel:
-        phi_check = phi_check == IN_NEW_FUNCTION ? IN_ENTRY_BLOCK : PHI_VALID;
+        adjacency_status =
+            adjacency_status == IN_NEW_FUNCTION ? IN_ENTRY_BLOCK : PHI_VALID;
         break;
       case SpvOpPhi:
-        if (phi_check != PHI_VALID) {
+        if (adjacency_status != PHI_VALID) {
           return _.diag(SPV_ERROR_INVALID_DATA, &inst)
                  << "OpPhi must appear within a non-entry block before all "
                  << "non-OpPhi instructions "
@@ -59,7 +65,7 @@ spv_result_t ValidateAdjacency(ValidationState_t& _) {
       case SpvOpLine:
         break;
       case SpvOpLoopMerge:
-        phi_check = PHI_INVALID;
+        adjacency_status = PHI_AND_VAR_INVALID;
         if (i != (instructions.size() - 1)) {
           switch (instructions[i + 1].opcode()) {
             case SpvOpBranch:
@@ -75,7 +81,7 @@ spv_result_t ValidateAdjacency(ValidationState_t& _) {
         }
         break;
       case SpvOpSelectionMerge:
-        phi_check = PHI_INVALID;
+        adjacency_status = PHI_AND_VAR_INVALID;
         if (i != (instructions.size() - 1)) {
           switch (instructions[i + 1].opcode()) {
             case SpvOpBranchConditional:
@@ -90,8 +96,16 @@ spv_result_t ValidateAdjacency(ValidationState_t& _) {
           }
         }
         break;
+      case SpvOpVariable:
+        if (inst.GetOperandAs<SpvStorageClass>(2) == SpvStorageClassFunction &&
+            adjacency_status != IN_ENTRY_BLOCK) {
+          return _.diag(SPV_ERROR_INVALID_DATA, &inst)
+                 << "All OpVariable instructions in a function must be the "
+                    "first instructions in the first block.";
+        }
+        break;
       default:
-        phi_check = PHI_INVALID;
+        adjacency_status = PHI_AND_VAR_INVALID;
         break;
     }
   }
diff --git a/test/opt/local_ssa_elim_test.cpp b/test/opt/local_ssa_elim_test.cpp
index 92a95f14b..cd371575e 100644
--- a/test/opt/local_ssa_elim_test.cpp
+++ b/test/opt/local_ssa_elim_test.cpp
@@ -1662,6 +1662,7 @@ TEST_F(LocalSSAElimTest, CompositeExtractProblem) {
 %_ptr_Function__struct_11 = OpTypePointer Function %_struct_11
           %2 = OpFunction %void None %4
          %33 = OpLabel
+         %66 = OpVariable %_ptr_Function__arr__struct_11_uint_3 Function
          %34 = OpLoad %_arr_v4float_uint_3 %16
          %35 = OpLoad %_arr_v4float_uint_3 %17
          %36 = OpLoad %_arr_v4float_uint_3 %18
@@ -1694,7 +1695,6 @@ TEST_F(LocalSSAElimTest, CompositeExtractProblem) {
          %63 = OpCompositeExtract %v2float %40 2
          %64 = OpCompositeConstruct %_struct_11 %57 %58 %59 %60 %61 %62 %63
          %65 = OpCompositeConstruct %_arr__struct_11_uint_3 %48 %56 %64
-         %66 = OpVariable %_ptr_Function__arr__struct_11_uint_3 Function
          %67 = OpLoad %uint %20
 
 ; CHECK OpStore {{%\d+}} [[store_source:%\d+]]
diff --git a/test/val/val_adjacency_test.cpp b/test/val/val_adjacency_test.cpp
index 5d3121383..10002ef34 100644
--- a/test/val/val_adjacency_test.cpp
+++ b/test/val/val_adjacency_test.cpp
@@ -120,6 +120,7 @@ std::string GenerateShaderCode(
 %zero = OpConstant %int 0
 %int_1 = OpConstant %int 1
 %func = OpTypeFunction %void
+%func_int = OpTypePointer Function %int
 %main = OpFunction %void None %func
 %main_entry = OpLabel
 )";
@@ -313,6 +314,68 @@ OpNop
                         "non-OpPhi instructions"));
 }
 
+TEST_F(ValidateAdjacency, OpVariableInFunctionGood) {
+  const std::string body = R"(
+OpLine %string 1 1
+%var = OpVariable %func_int Function
+OpLine %string 2 1
+OpNop
+OpLine %string 3 1
+OpNop
+)";
+
+  CompileSuccessfully(GenerateShaderCode(body));
+  EXPECT_EQ(SPV_SUCCESS, ValidateInstructions());
+}
+
+TEST_F(ValidateAdjacency, OpVariableInFunctionMultipleGood) {
+  const std::string body = R"(
+OpLine %string 1 1
+%1 = OpVariable %func_int Function
+OpLine %string 2 1
+%2 = OpVariable %func_int Function
+%3 = OpVariable %func_int Function
+OpNop
+OpLine %string 3 1
+OpNop
+)";
+
+  CompileSuccessfully(GenerateShaderCode(body));
+  EXPECT_EQ(SPV_SUCCESS, ValidateInstructions());
+}
+
+TEST_F(ValidateAdjacency, OpVariableInFunctionBad) {
+  const std::string body = R"(
+%1 = OpUndef %int
+%2 = OpVariable %func_int Function
+)";
+
+  CompileSuccessfully(GenerateShaderCode(body));
+  EXPECT_EQ(SPV_ERROR_INVALID_DATA, ValidateInstructions());
+  EXPECT_THAT(getDiagnosticString(),
+              HasSubstr("All OpVariable instructions in a function must be the "
+                        "first instructions"));
+}
+
+TEST_F(ValidateAdjacency, OpVariableInFunctionMultipleBad) {
+  const std::string body = R"(
+OpNop
+%1 = OpVariable %func_int Function
+OpLine %string 1 1
+%2 = OpVariable %func_int Function
+OpNop
+OpNop
+OpLine %string 2 1
+%3 = OpVariable %func_int Function
+)";
+
+  CompileSuccessfully(GenerateShaderCode(body));
+  EXPECT_EQ(SPV_ERROR_INVALID_DATA, ValidateInstructions());
+  EXPECT_THAT(getDiagnosticString(),
+              HasSubstr("All OpVariable instructions in a function must be the "
+                        "first instructions"));
+}
+
 TEST_F(ValidateAdjacency, OpLoopMergePreceedsOpBranchSuccess) {
   const std::string body = R"(
 OpBranch %loop