diff --git a/libsolidity/ast/ASTAnnotations.h b/libsolidity/ast/ASTAnnotations.h
index 027b48a30..97077c9a6 100644
--- a/libsolidity/ast/ASTAnnotations.h
+++ b/libsolidity/ast/ASTAnnotations.h
@@ -94,6 +94,7 @@ struct SourceUnitAnnotation: ASTAnnotation
 	SetOnce<std::map<ASTString, std::vector<Declaration const*>>> exportedSymbols;
 	/// Experimental features.
 	std::set<ExperimentalFeature> experimentalFeatures;
+	/// Using the new ABI coder. Set to `false` if using ABI coder v1.
 	SetOnce<bool> useABICoderV2;
 };
 
diff --git a/libsolidity/interface/CompilerStack.cpp b/libsolidity/interface/CompilerStack.cpp
index 7a4d37448..90c809e13 100644
--- a/libsolidity/interface/CompilerStack.cpp
+++ b/libsolidity/interface/CompilerStack.cpp
@@ -1249,6 +1249,14 @@ void CompilerStack::generateIR(ContractDefinition const& _contract)
 	if (!compiledContract.yulIR.empty())
 		return;
 
+	if (!*_contract.sourceUnit().annotation().useABICoderV2)
+		m_errorReporter.warning(
+			2066_error,
+			_contract.location(),
+			"Contract requests the ABI coder v1, which is incompatible with the IR. "
+			"Using ABI coder v2 instead."
+		);
+
 	string dependenciesSource;
 	for (auto const* dependency: _contract.annotation().contractDependencies)
 		generateIR(*dependency);
diff --git a/scripts/error_codes.py b/scripts/error_codes.py
index 9b106d0c0..bf4079b32 100755
--- a/scripts/error_codes.py
+++ b/scripts/error_codes.py
@@ -221,7 +221,7 @@ def examine_id_coverage(top_dir, source_id_to_file_names, new_ids_only=False):
 
     old_source_only_ids = {
         "1123", "1220", "1584", "1823",
-        "1988", "2657", "2800", "3356",
+        "1988", "2066", "2657", "2800", "3356",
         "3893", "3996", "4010", "4802",
         "5073", "5272", "5622", "7128",
         "7589", "7593", "7653", "8065", "8084", "8140",
diff --git a/test/cmdlineTests/exp_base_literal/input.sol b/test/cmdlineTests/exp_base_literal/input.sol
index 1f4d4dd7f..1c8408413 100644
--- a/test/cmdlineTests/exp_base_literal/input.sol
+++ b/test/cmdlineTests/exp_base_literal/input.sol
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0
 pragma solidity > 0.7.1;
+pragma abicoder v2;
 
 contract C {
 	function f(uint a, uint b, uint c, uint d) public pure returns (uint, int, uint, uint) {
diff --git a/test/cmdlineTests/exp_base_literal/output b/test/cmdlineTests/exp_base_literal/output
index 89815e804..8f39ff6c5 100644
--- a/test/cmdlineTests/exp_base_literal/output
+++ b/test/cmdlineTests/exp_base_literal/output
@@ -7,23 +7,23 @@ IR:
  *******************************************************/
 
 
-object "C_80" {
+object "C_81" {
     code {
         mstore(64, 128)
         if callvalue() { revert(0, 0) }
 
-        constructor_C_80()
+        constructor_C_81()
 
-        codecopy(0, dataoffset("C_80_deployed"), datasize("C_80_deployed"))
+        codecopy(0, dataoffset("C_81_deployed"), datasize("C_81_deployed"))
 
-        return(0, datasize("C_80_deployed"))
+        return(0, datasize("C_81_deployed"))
 
-        function constructor_C_80() {
+        function constructor_C_81() {
 
         }
 
     }
-    object "C_80_deployed" {
+    object "C_81_deployed" {
         code {
             mstore(64, 128)
 
@@ -37,7 +37,7 @@ object "C_80" {
                     // f(uint256,uint256,uint256,uint256)
                     if callvalue() { revert(0, 0) }
                     let param_0, param_1, param_2, param_3 :=  abi_decode_tuple_t_uint256t_uint256t_uint256t_uint256(4, calldatasize())
-                    let ret_0, ret_1, ret_2, ret_3 :=  fun_f_79(param_0, param_1, param_2, param_3)
+                    let ret_0, ret_1, ret_2, ret_3 :=  fun_f_80(param_0, param_1, param_2, param_3)
                     let memPos := allocateMemory(0)
                     let memEnd := abi_encode_tuple_t_uint256_t_int256_t_uint256_t_uint256__to_t_uint256_t_int256_t_uint256_t_uint256__fromStack(memPos , ret_0, ret_1, ret_2, ret_3)
                     return(memPos, sub(memEnd, memPos))
@@ -201,83 +201,83 @@ object "C_80" {
                 converted := cleanup_t_int256(value)
             }
 
-            function fun_f_79(vloc_a_3, vloc_b_5, vloc_c_7, vloc_d_9) -> vloc__12, vloc__14, vloc__16, vloc__18 {
+            function fun_f_80(vloc_a_4, vloc_b_6, vloc_c_8, vloc_d_10) -> vloc__13, vloc__15, vloc__17, vloc__19 {
                 let zero_value_for_type_t_uint256_1 := zero_value_for_split_t_uint256()
-                vloc__12 := zero_value_for_type_t_uint256_1
+                vloc__13 := zero_value_for_type_t_uint256_1
                 let zero_value_for_type_t_int256_2 := zero_value_for_split_t_int256()
-                vloc__14 := zero_value_for_type_t_int256_2
+                vloc__15 := zero_value_for_type_t_int256_2
                 let zero_value_for_type_t_uint256_3 := zero_value_for_split_t_uint256()
-                vloc__16 := zero_value_for_type_t_uint256_3
+                vloc__17 := zero_value_for_type_t_uint256_3
                 let zero_value_for_type_t_uint256_4 := zero_value_for_split_t_uint256()
-                vloc__18 := zero_value_for_type_t_uint256_4
+                vloc__19 := zero_value_for_type_t_uint256_4
 
-                let expr_22 := 0x02
-                let _5 := vloc_a_3
-                let expr_23 := _5
-                let _6 := convert_t_rational_2_by_1_to_t_uint256(expr_22)
-                let expr_24 := checked_exp_t_rational_2_by_1_t_uint256(expr_23)
-                let vloc_w_21 := expr_24
-                let expr_28 := 0x02
-                let expr_29 := 0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffe
-                let expr_30 := expr_29
-                let _7 := vloc_b_5
-                let expr_31 := _7
-                let _8 := convert_t_rational_minus_2_by_1_to_t_int256(expr_30)
-                let expr_32 := checked_exp_t_rational_minus_2_by_1_t_uint256(expr_31)
-                let vloc_x_27 := expr_32
-                let expr_36 := 0x0a
-                let _9 := vloc_c_7
-                let expr_37 := _9
-                let _10 := convert_t_rational_10_by_1_to_t_uint256(expr_36)
-                let expr_38 := checked_exp_t_rational_10_by_1_t_uint256(expr_37)
-                let vloc_y_35 := expr_38
-                let expr_46 := 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
-                let expr_47 := expr_46
-                let _11 := vloc_d_9
-                let expr_48 := _11
-                let _12 := convert_t_rational_115792089237316195423570985008687907853269984665640564039457584007913129639935_by_1_to_t_uint256(expr_47)
-                let expr_49 := checked_exp_t_rational_115792089237316195423570985008687907853269984665640564039457584007913129639935_by_1_t_uint256(expr_48)
-                let vloc_z_41 := expr_49
-                let expr_52 := 0x00
-                let expr_53 := expr_52
-                let _13 := vloc_a_3
-                let expr_54 := _13
-                let _14 := convert_t_rational_0_by_1_to_t_uint256(expr_53)
-                let expr_55 := checked_exp_t_rational_0_by_1_t_uint256(expr_54)
-                vloc_w_21 := expr_55
-                let expr_56 := expr_55
-                let expr_59 := 0x01
-                let expr_60 := 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
-                let expr_61 := expr_60
-                let _15 := vloc_b_5
-                let expr_62 := _15
-                let _16 := convert_t_rational_minus_1_by_1_to_t_int256(expr_61)
-                let expr_63 := checked_exp_t_rational_minus_1_by_1_t_uint256(expr_62)
-                vloc_x_27 := expr_63
-                let expr_64 := expr_63
-                let expr_67 := 0x01
-                let _17 := vloc_c_7
-                let expr_68 := _17
-                let _18 := convert_t_rational_1_by_1_to_t_uint256(expr_67)
-                let expr_69 := checked_exp_t_rational_1_by_1_t_uint256(expr_68)
-                vloc_y_35 := expr_69
-                let expr_70 := expr_69
-                let _19 := vloc_w_21
-                let expr_72 := _19
-                let expr_76_component_1 := expr_72
-                let _20 := vloc_x_27
-                let expr_73 := _20
-                let expr_76_component_2 := expr_73
-                let _21 := vloc_y_35
-                let expr_74 := _21
-                let expr_76_component_3 := expr_74
-                let _22 := vloc_z_41
-                let expr_75 := _22
-                let expr_76_component_4 := expr_75
-                vloc__12 := expr_76_component_1
-                vloc__14 := expr_76_component_2
-                vloc__16 := expr_76_component_3
-                vloc__18 := expr_76_component_4
+                let expr_23 := 0x02
+                let _5 := vloc_a_4
+                let expr_24 := _5
+                let _6 := convert_t_rational_2_by_1_to_t_uint256(expr_23)
+                let expr_25 := checked_exp_t_rational_2_by_1_t_uint256(expr_24)
+                let vloc_w_22 := expr_25
+                let expr_29 := 0x02
+                let expr_30 := 0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffe
+                let expr_31 := expr_30
+                let _7 := vloc_b_6
+                let expr_32 := _7
+                let _8 := convert_t_rational_minus_2_by_1_to_t_int256(expr_31)
+                let expr_33 := checked_exp_t_rational_minus_2_by_1_t_uint256(expr_32)
+                let vloc_x_28 := expr_33
+                let expr_37 := 0x0a
+                let _9 := vloc_c_8
+                let expr_38 := _9
+                let _10 := convert_t_rational_10_by_1_to_t_uint256(expr_37)
+                let expr_39 := checked_exp_t_rational_10_by_1_t_uint256(expr_38)
+                let vloc_y_36 := expr_39
+                let expr_47 := 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
+                let expr_48 := expr_47
+                let _11 := vloc_d_10
+                let expr_49 := _11
+                let _12 := convert_t_rational_115792089237316195423570985008687907853269984665640564039457584007913129639935_by_1_to_t_uint256(expr_48)
+                let expr_50 := checked_exp_t_rational_115792089237316195423570985008687907853269984665640564039457584007913129639935_by_1_t_uint256(expr_49)
+                let vloc_z_42 := expr_50
+                let expr_53 := 0x00
+                let expr_54 := expr_53
+                let _13 := vloc_a_4
+                let expr_55 := _13
+                let _14 := convert_t_rational_0_by_1_to_t_uint256(expr_54)
+                let expr_56 := checked_exp_t_rational_0_by_1_t_uint256(expr_55)
+                vloc_w_22 := expr_56
+                let expr_57 := expr_56
+                let expr_60 := 0x01
+                let expr_61 := 0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
+                let expr_62 := expr_61
+                let _15 := vloc_b_6
+                let expr_63 := _15
+                let _16 := convert_t_rational_minus_1_by_1_to_t_int256(expr_62)
+                let expr_64 := checked_exp_t_rational_minus_1_by_1_t_uint256(expr_63)
+                vloc_x_28 := expr_64
+                let expr_65 := expr_64
+                let expr_68 := 0x01
+                let _17 := vloc_c_8
+                let expr_69 := _17
+                let _18 := convert_t_rational_1_by_1_to_t_uint256(expr_68)
+                let expr_70 := checked_exp_t_rational_1_by_1_t_uint256(expr_69)
+                vloc_y_36 := expr_70
+                let expr_71 := expr_70
+                let _19 := vloc_w_22
+                let expr_73 := _19
+                let expr_77_component_1 := expr_73
+                let _20 := vloc_x_28
+                let expr_74 := _20
+                let expr_77_component_2 := expr_74
+                let _21 := vloc_y_36
+                let expr_75 := _21
+                let expr_77_component_3 := expr_75
+                let _22 := vloc_z_42
+                let expr_76 := _22
+                let expr_77_component_4 := expr_76
+                vloc__13 := expr_77_component_1
+                vloc__15 := expr_77_component_2
+                vloc__17 := expr_77_component_3
+                vloc__19 := expr_77_component_4
                 leave
 
             }
diff --git a/test/cmdlineTests/ir_compiler_inheritance_nosubobjects/input.sol b/test/cmdlineTests/ir_compiler_inheritance_nosubobjects/input.sol
index 8d523bd4d..097a2fbe9 100644
--- a/test/cmdlineTests/ir_compiler_inheritance_nosubobjects/input.sol
+++ b/test/cmdlineTests/ir_compiler_inheritance_nosubobjects/input.sol
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0
 pragma solidity >=0.6.0;
+pragma abicoder v2;
 
 contract C {
     constructor() {}
diff --git a/test/cmdlineTests/ir_compiler_inheritance_nosubobjects/output b/test/cmdlineTests/ir_compiler_inheritance_nosubobjects/output
index fd372367a..418676634 100644
--- a/test/cmdlineTests/ir_compiler_inheritance_nosubobjects/output
+++ b/test/cmdlineTests/ir_compiler_inheritance_nosubobjects/output
@@ -6,17 +6,17 @@ Optimized IR:
  *                !USE AT YOUR OWN RISK!               *
  *******************************************************/
 
-object "C_6" {
+object "C_7" {
     code {
         {
             mstore(64, 128)
             if callvalue() { revert(0, 0) }
-            let _1 := datasize("C_6_deployed")
-            codecopy(0, dataoffset("C_6_deployed"), _1)
+            let _1 := datasize("C_7_deployed")
+            codecopy(0, dataoffset("C_7_deployed"), _1)
             return(0, _1)
         }
     }
-    object "C_6_deployed" {
+    object "C_7_deployed" {
         code {
             {
                 mstore(64, 128)
@@ -34,17 +34,17 @@ Optimized IR:
  *                !USE AT YOUR OWN RISK!               *
  *******************************************************/
 
-object "D_9" {
+object "D_10" {
     code {
         {
             mstore(64, 128)
             if callvalue() { revert(0, 0) }
-            let _1 := datasize("D_9_deployed")
-            codecopy(0, dataoffset("D_9_deployed"), _1)
+            let _1 := datasize("D_10_deployed")
+            codecopy(0, dataoffset("D_10_deployed"), _1)
             return(0, _1)
         }
     }
-    object "D_9_deployed" {
+    object "D_10_deployed" {
         code {
             {
                 mstore(64, 128)
diff --git a/test/cmdlineTests/ir_compiler_subobjects/err b/test/cmdlineTests/ir_compiler_subobjects/err
index d4394af57..b300ec124 100644
--- a/test/cmdlineTests/ir_compiler_subobjects/err
+++ b/test/cmdlineTests/ir_compiler_subobjects/err
@@ -1,5 +1,5 @@
 Warning: Unused local variable.
- --> ir_compiler_subobjects/input.sol:7:9:
+ --> ir_compiler_subobjects/input.sol:8:9:
   |
-7 |         C c = new C();
+8 |         C c = new C();
   |         ^^^
diff --git a/test/cmdlineTests/ir_compiler_subobjects/input.sol b/test/cmdlineTests/ir_compiler_subobjects/input.sol
index 13f9f3c60..bad0fe74f 100644
--- a/test/cmdlineTests/ir_compiler_subobjects/input.sol
+++ b/test/cmdlineTests/ir_compiler_subobjects/input.sol
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0
 pragma solidity >=0.6.0;
+pragma abicoder v2;
 
 contract C {}
 contract D {
diff --git a/test/cmdlineTests/ir_compiler_subobjects/output b/test/cmdlineTests/ir_compiler_subobjects/output
index 7df119fa2..c0f66bfa3 100644
--- a/test/cmdlineTests/ir_compiler_subobjects/output
+++ b/test/cmdlineTests/ir_compiler_subobjects/output
@@ -6,17 +6,17 @@ Optimized IR:
  *                !USE AT YOUR OWN RISK!               *
  *******************************************************/
 
-object "C_2" {
+object "C_3" {
     code {
         {
             mstore(64, 128)
             if callvalue() { revert(0, 0) }
-            let _1 := datasize("C_2_deployed")
-            codecopy(0, dataoffset("C_2_deployed"), _1)
+            let _1 := datasize("C_3_deployed")
+            codecopy(0, dataoffset("C_3_deployed"), _1)
             return(0, _1)
         }
     }
-    object "C_2_deployed" {
+    object "C_3_deployed" {
         code {
             {
                 mstore(64, 128)
@@ -34,17 +34,17 @@ Optimized IR:
  *                !USE AT YOUR OWN RISK!               *
  *******************************************************/
 
-object "D_13" {
+object "D_14" {
     code {
         {
             mstore(64, 128)
             if callvalue() { revert(0, 0) }
-            let _1 := datasize("D_13_deployed")
-            codecopy(0, dataoffset("D_13_deployed"), _1)
+            let _1 := datasize("D_14_deployed")
+            codecopy(0, dataoffset("D_14_deployed"), _1)
             return(0, _1)
         }
     }
-    object "D_13_deployed" {
+    object "D_14_deployed" {
         code {
             {
                 mstore(64, 128)
@@ -55,10 +55,10 @@ object "D_13" {
                     {
                         if callvalue() { revert(_1, _1) }
                         if slt(add(calldatasize(), not(3)), _1) { revert(_1, _1) }
-                        let _2 := datasize("C_2")
+                        let _2 := datasize("C_3")
                         let _3 := add(128, _2)
                         if or(gt(_3, 0xffffffffffffffff), lt(_3, 128)) { invalid() }
-                        datacopy(128, dataoffset("C_2"), _2)
+                        datacopy(128, dataoffset("C_3"), _2)
                         if iszero(create(_1, 128, _2))
                         {
                             returndatacopy(_1, _1, returndatasize())
@@ -77,17 +77,17 @@ object "D_13" {
                 mstore(64, newFreePtr)
             }
         }
-        object "C_2" {
+        object "C_3" {
             code {
                 {
                     mstore(64, 128)
                     if callvalue() { revert(0, 0) }
-                    let _1 := datasize("C_2_deployed")
-                    codecopy(0, dataoffset("C_2_deployed"), _1)
+                    let _1 := datasize("C_3_deployed")
+                    codecopy(0, dataoffset("C_3_deployed"), _1)
                     return(0, _1)
                 }
             }
-            object "C_2_deployed" {
+            object "C_3_deployed" {
                 code {
                     {
                         mstore(64, 128)
diff --git a/test/cmdlineTests/ir_with_assembly_no_memoryguard_creation/input.sol b/test/cmdlineTests/ir_with_assembly_no_memoryguard_creation/input.sol
index 6dd033f13..aca9b3bef 100644
--- a/test/cmdlineTests/ir_with_assembly_no_memoryguard_creation/input.sol
+++ b/test/cmdlineTests/ir_with_assembly_no_memoryguard_creation/input.sol
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0
 pragma solidity >=0.0.0;
+pragma abicoder v2;
 
 contract D {
     constructor() { assembly {}}
diff --git a/test/cmdlineTests/ir_with_assembly_no_memoryguard_creation/output b/test/cmdlineTests/ir_with_assembly_no_memoryguard_creation/output
index 35c3f4473..e4ad6b298 100644
--- a/test/cmdlineTests/ir_with_assembly_no_memoryguard_creation/output
+++ b/test/cmdlineTests/ir_with_assembly_no_memoryguard_creation/output
@@ -6,17 +6,17 @@ Optimized IR:
  *                !USE AT YOUR OWN RISK!               *
  *******************************************************/
 
-object "D_11" {
+object "D_12" {
     code {
         {
             mstore(64, 128)
             if callvalue() { revert(0, 0) }
-            let _1 := datasize("D_11_deployed")
-            codecopy(0, dataoffset("D_11_deployed"), _1)
+            let _1 := datasize("D_12_deployed")
+            codecopy(0, dataoffset("D_12_deployed"), _1)
             return(0, _1)
         }
     }
-    object "D_11_deployed" {
+    object "D_12_deployed" {
         code {
             {
                 mstore(64, 128)
diff --git a/test/cmdlineTests/ir_with_assembly_no_memoryguard_runtime/input.sol b/test/cmdlineTests/ir_with_assembly_no_memoryguard_runtime/input.sol
index caef2b75e..e217f9cbb 100644
--- a/test/cmdlineTests/ir_with_assembly_no_memoryguard_runtime/input.sol
+++ b/test/cmdlineTests/ir_with_assembly_no_memoryguard_runtime/input.sol
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0
 pragma solidity >=0.0.0;
+pragma abicoder v2;
 
 contract D {
     function f() public pure {
diff --git a/test/cmdlineTests/ir_with_assembly_no_memoryguard_runtime/output b/test/cmdlineTests/ir_with_assembly_no_memoryguard_runtime/output
index 601d941a2..cf559e4bd 100644
--- a/test/cmdlineTests/ir_with_assembly_no_memoryguard_runtime/output
+++ b/test/cmdlineTests/ir_with_assembly_no_memoryguard_runtime/output
@@ -6,17 +6,17 @@ Optimized IR:
  *                !USE AT YOUR OWN RISK!               *
  *******************************************************/
 
-object "D_7" {
+object "D_8" {
     code {
         {
             mstore(64, 128)
             if callvalue() { revert(0, 0) }
-            let _1 := datasize("D_7_deployed")
-            codecopy(0, dataoffset("D_7_deployed"), _1)
+            let _1 := datasize("D_8_deployed")
+            codecopy(0, dataoffset("D_8_deployed"), _1)
             return(0, _1)
         }
     }
-    object "D_7_deployed" {
+    object "D_8_deployed" {
         code {
             {
                 mstore(64, 128)
diff --git a/test/cmdlineTests/optimizer_array_sload/input.sol b/test/cmdlineTests/optimizer_array_sload/input.sol
index 3c8c3d212..94f42219a 100644
--- a/test/cmdlineTests/optimizer_array_sload/input.sol
+++ b/test/cmdlineTests/optimizer_array_sload/input.sol
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0
 pragma solidity >=0.0;
+pragma abicoder v2;
 
 contract Arraysum {
 	uint256[] values;
diff --git a/test/cmdlineTests/optimizer_array_sload/output b/test/cmdlineTests/optimizer_array_sload/output
index 901d1b22a..331c71f23 100644
--- a/test/cmdlineTests/optimizer_array_sload/output
+++ b/test/cmdlineTests/optimizer_array_sload/output
@@ -6,17 +6,17 @@ Optimized IR:
  *                !USE AT YOUR OWN RISK!               *
  *******************************************************/
 
-object "Arraysum_33" {
+object "Arraysum_34" {
     code {
         {
             mstore(64, 128)
             if callvalue() { revert(0, 0) }
-            let _1 := datasize("Arraysum_33_deployed")
-            codecopy(0, dataoffset("Arraysum_33_deployed"), _1)
+            let _1 := datasize("Arraysum_34_deployed")
+            codecopy(0, dataoffset("Arraysum_34_deployed"), _1)
             return(0, _1)
         }
     }
-    object "Arraysum_33_deployed" {
+    object "Arraysum_34_deployed" {
         code {
             {
                 mstore(64, 128)
diff --git a/test/cmdlineTests/standard_ewasm_requested/input.json b/test/cmdlineTests/standard_ewasm_requested/input.json
index d3c6cc892..53dcc68ee 100644
--- a/test/cmdlineTests/standard_ewasm_requested/input.json
+++ b/test/cmdlineTests/standard_ewasm_requested/input.json
@@ -4,7 +4,7 @@
 	{
 		"A":
 		{
-			"content": "// SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; contract C { }"
+			"content": "// SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; pragma abicoder v2; contract C { }"
 		}
 	},
 	"settings":
diff --git a/test/cmdlineTests/standard_ewasm_requested/output.json b/test/cmdlineTests/standard_ewasm_requested/output.json
index f8ed91e85..b63bc50dc 100644
--- a/test/cmdlineTests/standard_ewasm_requested/output.json
+++ b/test/cmdlineTests/standard_ewasm_requested/output.json
@@ -1,7 +1,7 @@
-{"contracts":{"A":{"C":{"ewasm":{"wasm":"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","wast":"(module
+{"contracts":{"A":{"C":{"ewasm":{"wasm":"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","wast":"(module
     ;; custom section for sub-module
-    ;; The Keccak-256 hash of the text representation of \"C_2_deployed\": 0289c074ac70ccfdbeb7817862087cc066a9f7707de1a981bb8b5b12dd2ce4e9
-    ;; (@custom \"C_2_deployed\" \"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\")
+    ;; The Keccak-256 hash of the text representation of \"C_3_deployed\": 0289c074ac70ccfdbeb7817862087cc066a9f7707de1a981bb8b5b12dd2ce4e9
+    ;; (@custom \"C_3_deployed\" \"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\")
     (import \"ethereum\" \"codeCopy\" (func $eth.codeCopy (param i32 i32 i32)))
     (import \"ethereum\" \"revert\" (func $eth.revert (param i32 i32)))
     (import \"ethereum\" \"getCallValue\" (func $eth.getCallValue (param i32)))
@@ -35,8 +35,8 @@
         (local.set $z3 (call $bswap64 (i64.load (i32.add (i32.const 0) (i32.const 16)))))
         (if (i32.eqz (i64.eqz (i64.or (i64.or (local.get $z1) (local.get $z2)) (i64.or (local.get $z3) (call $bswap64 (i64.load (i32.add (i32.const 0) (i32.const 24)))))))) (then
             (call $revert (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1))))
-        (local.set $_3 (datasize \"C_2_deployed\"))
-        (call $codecopy (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (dataoffset \"C_2_deployed\") (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_3))
+        (local.set $_3 (datasize \"C_3_deployed\"))
+        (call $codecopy (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (dataoffset \"C_3_deployed\") (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_3))
         (call $return (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_1) (local.get $_3))
     )
 )
diff --git a/test/cmdlineTests/standard_ewasm_requested_abstract/input.json b/test/cmdlineTests/standard_ewasm_requested_abstract/input.json
index 313fa478c..2ee666fe2 100644
--- a/test/cmdlineTests/standard_ewasm_requested_abstract/input.json
+++ b/test/cmdlineTests/standard_ewasm_requested_abstract/input.json
@@ -4,7 +4,7 @@
 	{
 		"A":
 		{
-			"content": "// SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; abstract contract C { }"
+			"content": "// SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; pragma abicoder v2; abstract contract C { }"
 		}
 	},
 	"settings":
diff --git a/test/cmdlineTests/standard_irOptimized_requested/input.json b/test/cmdlineTests/standard_irOptimized_requested/input.json
index 09aa37bae..48e5c7b0a 100644
--- a/test/cmdlineTests/standard_irOptimized_requested/input.json
+++ b/test/cmdlineTests/standard_irOptimized_requested/input.json
@@ -4,7 +4,7 @@
 	{
 		"A":
 		{
-			"content": "// SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; contract C { function f() public pure {} }"
+			"content": "// SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; pragma abicoder v2; contract C { function f() public pure {} }"
 		}
 	},
 	"settings":
diff --git a/test/cmdlineTests/standard_irOptimized_requested/output.json b/test/cmdlineTests/standard_irOptimized_requested/output.json
index dd7c82123..1da912297 100644
--- a/test/cmdlineTests/standard_irOptimized_requested/output.json
+++ b/test/cmdlineTests/standard_irOptimized_requested/output.json
@@ -5,17 +5,17 @@
  *                !USE AT YOUR OWN RISK!               *
  *******************************************************/
 
-object \"C_6\" {
+object \"C_7\" {
     code {
         mstore(64, 128)
         if callvalue() { revert(0, 0) }
-        constructor_C_6()
-        codecopy(0, dataoffset(\"C_6_deployed\"), datasize(\"C_6_deployed\"))
-        return(0, datasize(\"C_6_deployed\"))
-        function constructor_C_6()
+        constructor_C_7()
+        codecopy(0, dataoffset(\"C_7_deployed\"), datasize(\"C_7_deployed\"))
+        return(0, datasize(\"C_7_deployed\"))
+        function constructor_C_7()
         { }
     }
-    object \"C_6_deployed\" {
+    object \"C_7_deployed\" {
         code {
             mstore(64, 128)
             if iszero(lt(calldatasize(), 4))
@@ -25,7 +25,7 @@ object \"C_6\" {
                 case 0x26121ff0 {
                     if callvalue() { revert(0, 0) }
                     abi_decode_tuple_(4, calldatasize())
-                    fun_f_5()
+                    fun_f_6()
                     let memPos := allocateMemory(0)
                     let memEnd := abi_encode_tuple__to__fromStack(memPos)
                     return(memPos, sub(memEnd, memPos))
@@ -47,7 +47,7 @@ object \"C_6\" {
                 if or(gt(newFreePtr, 0xffffffffffffffff), lt(newFreePtr, memPtr)) { panic_error() }
                 mstore(64, newFreePtr)
             }
-            function fun_f_5()
+            function fun_f_6()
             { }
             function panic_error()
             { invalid() }
diff --git a/test/cmdlineTests/standard_ir_requested/input.json b/test/cmdlineTests/standard_ir_requested/input.json
index cc0a91df9..6eb5295c5 100644
--- a/test/cmdlineTests/standard_ir_requested/input.json
+++ b/test/cmdlineTests/standard_ir_requested/input.json
@@ -4,7 +4,7 @@
 	{
 		"A":
 		{
-			"content": "// SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; contract C { function f() public pure {} }"
+			"content": "// SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; pragma abicoder v2; contract C { function f() public pure {} }"
 		}
 	},
 	"settings":
diff --git a/test/cmdlineTests/standard_ir_requested/output.json b/test/cmdlineTests/standard_ir_requested/output.json
index d46256ee7..c5a91cbd7 100644
--- a/test/cmdlineTests/standard_ir_requested/output.json
+++ b/test/cmdlineTests/standard_ir_requested/output.json
@@ -6,23 +6,23 @@
  *******************************************************/
 
 
-object \"C_6\" {
+object \"C_7\" {
     code {
         mstore(64, 128)
         if callvalue() { revert(0, 0) }
 
-        constructor_C_6()
+        constructor_C_7()
 
-        codecopy(0, dataoffset(\"C_6_deployed\"), datasize(\"C_6_deployed\"))
+        codecopy(0, dataoffset(\"C_7_deployed\"), datasize(\"C_7_deployed\"))
 
-        return(0, datasize(\"C_6_deployed\"))
+        return(0, datasize(\"C_7_deployed\"))
 
-        function constructor_C_6() {
+        function constructor_C_7() {
 
         }
 
     }
-    object \"C_6_deployed\" {
+    object \"C_7_deployed\" {
         code {
             mstore(64, 128)
 
@@ -36,7 +36,7 @@ object \"C_6\" {
                     // f()
                     if callvalue() { revert(0, 0) }
                     abi_decode_tuple_(4, calldatasize())
-                    fun_f_5()
+                    fun_f_6()
                     let memPos := allocateMemory(0)
                     let memEnd := abi_encode_tuple__to__fromStack(memPos  )
                     return(memPos, sub(memEnd, memPos))
@@ -65,7 +65,7 @@ object \"C_6\" {
                 mstore(64, newFreePtr)
             }
 
-            function fun_f_5() {
+            function fun_f_6() {
 
             }
 
diff --git a/test/cmdlineTests/standard_viair_requested/input.json b/test/cmdlineTests/standard_viair_requested/input.json
index 6a970357e..76ae807a6 100644
--- a/test/cmdlineTests/standard_viair_requested/input.json
+++ b/test/cmdlineTests/standard_viair_requested/input.json
@@ -4,7 +4,7 @@
 	{
 		"A":
 		{
-			"content": "// SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; contract C {} contract D { function f() public { C c = new C(); } }"
+			"content": "// SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; pragma abicoder v2; contract C {} contract D { function f() public { C c = new C(); } }"
 		}
 	},
 	"settings":
diff --git a/test/cmdlineTests/standard_viair_requested/output.json b/test/cmdlineTests/standard_viair_requested/output.json
index f48dcf52f..5f280417c 100644
--- a/test/cmdlineTests/standard_viair_requested/output.json
+++ b/test/cmdlineTests/standard_viair_requested/output.json
@@ -6,23 +6,23 @@
  *******************************************************/
 
 
-object \"C_2\" {
+object \"C_3\" {
     code {
         mstore(64, 128)
         if callvalue() { revert(0, 0) }
 
-        constructor_C_2()
+        constructor_C_3()
 
-        codecopy(0, dataoffset(\"C_2_deployed\"), datasize(\"C_2_deployed\"))
+        codecopy(0, dataoffset(\"C_3_deployed\"), datasize(\"C_3_deployed\"))
 
-        return(0, datasize(\"C_2_deployed\"))
+        return(0, datasize(\"C_3_deployed\"))
 
-        function constructor_C_2() {
+        function constructor_C_3() {
 
         }
 
     }
-    object \"C_2_deployed\" {
+    object \"C_3_deployed\" {
         code {
             mstore(64, 128)
 
@@ -57,23 +57,23 @@ object \"C_2\" {
  *******************************************************/
 
 
-object \"D_13\" {
+object \"D_14\" {
     code {
         mstore(64, 128)
         if callvalue() { revert(0, 0) }
 
-        constructor_D_13()
+        constructor_D_14()
 
-        codecopy(0, dataoffset(\"D_13_deployed\"), datasize(\"D_13_deployed\"))
+        codecopy(0, dataoffset(\"D_14_deployed\"), datasize(\"D_14_deployed\"))
 
-        return(0, datasize(\"D_13_deployed\"))
+        return(0, datasize(\"D_14_deployed\"))
 
-        function constructor_D_13() {
+        function constructor_D_14() {
 
         }
 
     }
-    object \"D_13_deployed\" {
+    object \"D_14_deployed\" {
         code {
             mstore(64, 128)
 
@@ -87,7 +87,7 @@ object \"D_13\" {
                     // f()
                     if callvalue() { revert(0, 0) }
                     abi_decode_tuple_(4, calldatasize())
-                    fun_f_12()
+                    fun_f_13()
                     let memPos := allocateMemory(0)
                     let memEnd := abi_encode_tuple__to__fromStack(memPos  )
                     return(memPos, sub(memEnd, memPos))
@@ -120,20 +120,20 @@ object \"D_13\" {
                 memPtr := mload(64)
             }
 
-            function fun_f_12() {
+            function fun_f_13() {
 
                 let _1 := allocateTemporaryMemory()
-                let _2 := add(_1, datasize(\"C_2\"))
+                let _2 := add(_1, datasize(\"C_3\"))
                 if or(gt(_2, 0xffffffffffffffff), lt(_2, _1)) { panic_error() }
-                datacopy(_1, dataoffset(\"C_2\"), datasize(\"C_2\"))
+                datacopy(_1, dataoffset(\"C_3\"), datasize(\"C_3\"))
                 _2 := abi_encode_tuple__to__fromStack(_2)
 
-                let expr_9_address := create(0, _1, sub(_2, _1))
+                let expr_10_address := create(0, _1, sub(_2, _1))
 
-                if iszero(expr_9_address) { revert_forward_1() }
+                if iszero(expr_10_address) { revert_forward_1() }
 
                 releaseTemporaryMemory()
-                let vloc_c_6_address := expr_9_address
+                let vloc_c_7_address := expr_10_address
 
             }
 
@@ -164,23 +164,23 @@ object \"D_13\" {
         *                !USE AT YOUR OWN RISK!               *
         *******************************************************/
 
-        object \"C_2\" {
+        object \"C_3\" {
             code {
                 mstore(64, 128)
                 if callvalue() { revert(0, 0) }
 
-                constructor_C_2()
+                constructor_C_3()
 
-                codecopy(0, dataoffset(\"C_2_deployed\"), datasize(\"C_2_deployed\"))
+                codecopy(0, dataoffset(\"C_3_deployed\"), datasize(\"C_3_deployed\"))
 
-                return(0, datasize(\"C_2_deployed\"))
+                return(0, datasize(\"C_3_deployed\"))
 
-                function constructor_C_2() {
+                function constructor_C_3() {
 
                 }
 
             }
-            object \"C_2_deployed\" {
+            object \"C_3_deployed\" {
                 code {
                     mstore(64, 128)
 
@@ -211,7 +211,7 @@ object \"D_13\" {
 
 }
 
-"}}},"errors":[{"component":"general","errorCode":"2072","formattedMessage":"A:2:73: Warning: Unused local variable.
-pragma solidity >=0.0; contract C {} contract D { function f() public { C c = new C(); } }
-                                                                        ^-^
-","message":"Unused local variable.","severity":"warning","sourceLocation":{"end":111,"file":"A","start":108},"type":"Warning"}],"sources":{"A":{"id":0}}}
+"}}},"errors":[{"component":"general","errorCode":"2072","formattedMessage":"A:2:93: Warning: Unused local variable.
+pragma solidity >=0.0; pragma abicoder v2; contract C {} contract D { function f() public { C c = new C(); } }
+                                                                                            ^-^
+","message":"Unused local variable.","severity":"warning","sourceLocation":{"end":131,"file":"A","start":128},"type":"Warning"}],"sources":{"A":{"id":0}}}
diff --git a/test/cmdlineTests/viair_abicoder_v1/args b/test/cmdlineTests/viair_abicoder_v1/args
new file mode 100644
index 000000000..e869749f2
--- /dev/null
+++ b/test/cmdlineTests/viair_abicoder_v1/args
@@ -0,0 +1 @@
+--ir --error-codes
diff --git a/test/cmdlineTests/viair_abicoder_v1/err b/test/cmdlineTests/viair_abicoder_v1/err
new file mode 100644
index 000000000..55f8ba4b9
--- /dev/null
+++ b/test/cmdlineTests/viair_abicoder_v1/err
@@ -0,0 +1,5 @@
+Warning (2066): Contract requests the ABI coder v1, which is incompatible with the IR. Using ABI coder v2 instead.
+ --> viair_abicoder_v1/input.sol:4:1:
+  |
+4 | contract test {
+  | ^ (Relevant source part starts here and spans across multiple lines).
diff --git a/test/cmdlineTests/viair_abicoder_v1/input.sol b/test/cmdlineTests/viair_abicoder_v1/input.sol
new file mode 100644
index 000000000..198e40e16
--- /dev/null
+++ b/test/cmdlineTests/viair_abicoder_v1/input.sol
@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: GPL-3.0
+pragma solidity >=0.0;
+pragma abicoder v1;
+contract test {
+    function f() public pure returns (bool) {
+        return true;
+    }
+}
diff --git a/test/cmdlineTests/viair_abicoder_v1/output b/test/cmdlineTests/viair_abicoder_v1/output
new file mode 100644
index 000000000..2aec15e28
--- /dev/null
+++ b/test/cmdlineTests/viair_abicoder_v1/output
@@ -0,0 +1,108 @@
+IR:
+/*******************************************************
+ *                       WARNING                       *
+ *  Solidity to Yul compilation is still EXPERIMENTAL  *
+ *       It can result in LOSS OF FUNDS or worse       *
+ *                !USE AT YOUR OWN RISK!               *
+ *******************************************************/
+
+
+object "test_11" {
+    code {
+        mstore(64, 128)
+        if callvalue() { revert(0, 0) }
+
+        constructor_test_11()
+
+        codecopy(0, dataoffset("test_11_deployed"), datasize("test_11_deployed"))
+
+        return(0, datasize("test_11_deployed"))
+
+        function constructor_test_11() {
+
+        }
+
+    }
+    object "test_11_deployed" {
+        code {
+            mstore(64, 128)
+
+            if iszero(lt(calldatasize(), 4))
+            {
+                let selector := shift_right_224_unsigned(calldataload(0))
+                switch selector
+
+                case 0x26121ff0
+                {
+                    // f()
+                    if callvalue() { revert(0, 0) }
+                    abi_decode_tuple_(4, calldatasize())
+                    let ret_0 :=  fun_f_10()
+                    let memPos := allocateMemory(0)
+                    let memEnd := abi_encode_tuple_t_bool__to_t_bool__fromStack(memPos , ret_0)
+                    return(memPos, sub(memEnd, memPos))
+                }
+
+                default {}
+            }
+            if iszero(calldatasize()) {  }
+            revert(0, 0)
+
+            function abi_decode_tuple_(headStart, dataEnd)   {
+                if slt(sub(dataEnd, headStart), 0) { revert(0, 0) }
+
+            }
+
+            function abi_encode_t_bool_to_t_bool_fromStack(value, pos) {
+                mstore(pos, cleanup_t_bool(value))
+            }
+
+            function abi_encode_tuple_t_bool__to_t_bool__fromStack(headStart , value0) -> tail {
+                tail := add(headStart, 32)
+
+                abi_encode_t_bool_to_t_bool_fromStack(value0,  add(headStart, 0))
+
+            }
+
+            function allocateMemory(size) -> memPtr {
+                memPtr := mload(64)
+                let newFreePtr := add(memPtr, size)
+                // protect against overflow
+                if or(gt(newFreePtr, 0xffffffffffffffff), lt(newFreePtr, memPtr)) { panic_error() }
+                mstore(64, newFreePtr)
+            }
+
+            function cleanup_t_bool(value) -> cleaned {
+                cleaned := iszero(iszero(value))
+            }
+
+            function fun_f_10() -> vloc__5 {
+                let zero_value_for_type_t_bool_1 := zero_value_for_split_t_bool()
+                vloc__5 := zero_value_for_type_t_bool_1
+
+                let expr_7 := 0x01
+                vloc__5 := expr_7
+                leave
+
+            }
+
+            function panic_error() {
+                invalid()
+            }
+
+            function shift_right_224_unsigned(value) -> newValue {
+                newValue :=
+
+                shr(224, value)
+
+            }
+
+            function zero_value_for_split_t_bool() -> ret {
+                ret := 0
+            }
+
+        }
+
+    }
+
+}
diff --git a/test/cmdlineTests/viair_subobjects/err b/test/cmdlineTests/viair_subobjects/err
index c355ba16e..5046525be 100644
--- a/test/cmdlineTests/viair_subobjects/err
+++ b/test/cmdlineTests/viair_subobjects/err
@@ -1,5 +1,5 @@
 Warning: Unused local variable.
- --> viair_subobjects/input.sol:7:9:
+ --> viair_subobjects/input.sol:8:9:
   |
-7 |         C c = new C();
+8 |         C c = new C();
   |         ^^^
diff --git a/test/cmdlineTests/viair_subobjects/input.sol b/test/cmdlineTests/viair_subobjects/input.sol
index 13f9f3c60..bad0fe74f 100644
--- a/test/cmdlineTests/viair_subobjects/input.sol
+++ b/test/cmdlineTests/viair_subobjects/input.sol
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0
 pragma solidity >=0.6.0;
+pragma abicoder v2;
 
 contract C {}
 contract D {
diff --git a/test/cmdlineTests/viair_subobjects/output b/test/cmdlineTests/viair_subobjects/output
index 91928ffb7..c3b5a4cea 100644
--- a/test/cmdlineTests/viair_subobjects/output
+++ b/test/cmdlineTests/viair_subobjects/output
@@ -12,17 +12,17 @@ Optimized IR:
  *                !USE AT YOUR OWN RISK!               *
  *******************************************************/
 
-object "C_2" {
+object "C_3" {
     code {
         {
             mstore(64, 128)
             if callvalue() { revert(0, 0) }
-            let _1 := datasize("C_2_deployed")
-            codecopy(0, dataoffset("C_2_deployed"), _1)
+            let _1 := datasize("C_3_deployed")
+            codecopy(0, dataoffset("C_3_deployed"), _1)
             return(0, _1)
         }
     }
-    object "C_2_deployed" {
+    object "C_3_deployed" {
         code {
             {
                 mstore(64, 128)
@@ -46,17 +46,17 @@ Optimized IR:
  *                !USE AT YOUR OWN RISK!               *
  *******************************************************/
 
-object "D_13" {
+object "D_14" {
     code {
         {
             mstore(64, 128)
             if callvalue() { revert(0, 0) }
-            let _1 := datasize("D_13_deployed")
-            codecopy(0, dataoffset("D_13_deployed"), _1)
+            let _1 := datasize("D_14_deployed")
+            codecopy(0, dataoffset("D_14_deployed"), _1)
             return(0, _1)
         }
     }
-    object "D_13_deployed" {
+    object "D_14_deployed" {
         code {
             {
                 mstore(64, 128)
@@ -67,10 +67,10 @@ object "D_13" {
                     {
                         if callvalue() { revert(_1, _1) }
                         if slt(add(calldatasize(), not(3)), _1) { revert(_1, _1) }
-                        let _2 := datasize("C_2")
+                        let _2 := datasize("C_3")
                         let _3 := add(128, _2)
                         if or(gt(_3, 0xffffffffffffffff), lt(_3, 128)) { invalid() }
-                        datacopy(128, dataoffset("C_2"), _2)
+                        datacopy(128, dataoffset("C_3"), _2)
                         if iszero(create(_1, 128, _2))
                         {
                             returndatacopy(_1, _1, returndatasize())
@@ -89,17 +89,17 @@ object "D_13" {
                 mstore(64, newFreePtr)
             }
         }
-        object "C_2" {
+        object "C_3" {
             code {
                 {
                     mstore(64, 128)
                     if callvalue() { revert(0, 0) }
-                    let _1 := datasize("C_2_deployed")
-                    codecopy(0, dataoffset("C_2_deployed"), _1)
+                    let _1 := datasize("C_3_deployed")
+                    codecopy(0, dataoffset("C_3_deployed"), _1)
                     return(0, _1)
                 }
             }
-            object "C_2_deployed" {
+            object "C_3_deployed" {
                 code {
                     {
                         mstore(64, 128)
diff --git a/test/cmdlineTests/yul_optimizer_steps/input.sol b/test/cmdlineTests/yul_optimizer_steps/input.sol
index c93363e41..260b21cd5 100644
--- a/test/cmdlineTests/yul_optimizer_steps/input.sol
+++ b/test/cmdlineTests/yul_optimizer_steps/input.sol
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0
 pragma solidity >=0.0;
+pragma abicoder v2;
 
 contract C
 {
diff --git a/test/cmdlineTests/yul_optimizer_steps/output b/test/cmdlineTests/yul_optimizer_steps/output
index 847c731e9..c06add7c7 100644
--- a/test/cmdlineTests/yul_optimizer_steps/output
+++ b/test/cmdlineTests/yul_optimizer_steps/output
@@ -6,16 +6,16 @@ Optimized IR:
  *                !USE AT YOUR OWN RISK!               *
  *******************************************************/
 
-object "C_6" {
+object "C_7" {
     code {
         {
             mstore(64, 128)
             if callvalue() { revert(0, 0) }
-            codecopy(0, dataoffset("C_6_deployed"), datasize("C_6_deployed"))
-            return(0, datasize("C_6_deployed"))
+            codecopy(0, dataoffset("C_7_deployed"), datasize("C_7_deployed"))
+            return(0, datasize("C_7_deployed"))
         }
     }
-    object "C_6_deployed" {
+    object "C_7_deployed" {
         code {
             {
                 mstore(64, 128)
diff --git a/test/cmdlineTests/yul_string_format_ascii/input.json b/test/cmdlineTests/yul_string_format_ascii/input.json
index 0eba555c9..7b86b65cd 100644
--- a/test/cmdlineTests/yul_string_format_ascii/input.json
+++ b/test/cmdlineTests/yul_string_format_ascii/input.json
@@ -4,7 +4,7 @@
 	{
 		"A":
 		{
-			"content": "//SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; contract C { function f() external pure returns (string memory) { return \"abcabc\"; } }"
+			"content": "//SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; pragma abicoder v2; contract C { function f() external pure returns (string memory) { return \"abcabc\"; } }"
 		}
 	},
 	"settings":
diff --git a/test/cmdlineTests/yul_string_format_ascii/output.json b/test/cmdlineTests/yul_string_format_ascii/output.json
index b6615773f..f00bb751c 100644
--- a/test/cmdlineTests/yul_string_format_ascii/output.json
+++ b/test/cmdlineTests/yul_string_format_ascii/output.json
@@ -6,23 +6,23 @@
  *******************************************************/
 
 
-object \"C_10\" {
+object \"C_11\" {
     code {
         mstore(64, 128)
         if callvalue() { revert(0, 0) }
 
-        constructor_C_10()
+        constructor_C_11()
 
-        codecopy(0, dataoffset(\"C_10_deployed\"), datasize(\"C_10_deployed\"))
+        codecopy(0, dataoffset(\"C_11_deployed\"), datasize(\"C_11_deployed\"))
 
-        return(0, datasize(\"C_10_deployed\"))
+        return(0, datasize(\"C_11_deployed\"))
 
-        function constructor_C_10() {
+        function constructor_C_11() {
 
         }
 
     }
-    object \"C_10_deployed\" {
+    object \"C_11_deployed\" {
         code {
             mstore(64, 128)
 
@@ -36,7 +36,7 @@ object \"C_10\" {
                     // f()
                     if callvalue() { revert(0, 0) }
                     abi_decode_tuple_(4, calldatasize())
-                    let ret_0 :=  fun_f_9()
+                    let ret_0 :=  fun_f_10()
                     let memPos := allocateMemory(0)
                     let memEnd := abi_encode_tuple_t_string_memory_ptr__to_t_string_memory_ptr__fromStack(memPos , ret_0)
                     return(memPos, sub(memEnd, memPos))
@@ -107,11 +107,11 @@ object \"C_10\" {
                 }
             }
 
-            function fun_f_9() -> vloc__4_mpos {
+            function fun_f_10() -> vloc__5_mpos {
                 let zero_value_for_type_t_string_memory_ptr_1_mpos := zero_value_for_split_t_string_memory_ptr()
-                vloc__4_mpos := zero_value_for_type_t_string_memory_ptr_1_mpos
+                vloc__5_mpos := zero_value_for_type_t_string_memory_ptr_1_mpos
 
-                vloc__4_mpos := convert_t_stringliteral_9f0adad0a59b05d2e04a1373342b10b9eb16c57c164c8a3bfcbf46dccee39a21_to_t_string_memory_ptr()
+                vloc__5_mpos := convert_t_stringliteral_9f0adad0a59b05d2e04a1373342b10b9eb16c57c164c8a3bfcbf46dccee39a21_to_t_string_memory_ptr()
                 leave
 
             }
diff --git a/test/cmdlineTests/yul_string_format_ascii_bytes32/input.json b/test/cmdlineTests/yul_string_format_ascii_bytes32/input.json
index 3dbcdb819..cb9318f33 100644
--- a/test/cmdlineTests/yul_string_format_ascii_bytes32/input.json
+++ b/test/cmdlineTests/yul_string_format_ascii_bytes32/input.json
@@ -4,7 +4,7 @@
 	{
 		"A":
 		{
-			"content": "//SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; contract C { function f() external pure returns (bytes32) { return \"abcabc\"; } }"
+			"content": "//SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; pragma abicoder v2; contract C { function f() external pure returns (bytes32) { return \"abcabc\"; } }"
 		}
 	},
 	"settings":
diff --git a/test/cmdlineTests/yul_string_format_ascii_bytes32/output.json b/test/cmdlineTests/yul_string_format_ascii_bytes32/output.json
index 457a301ca..bab7235d2 100644
--- a/test/cmdlineTests/yul_string_format_ascii_bytes32/output.json
+++ b/test/cmdlineTests/yul_string_format_ascii_bytes32/output.json
@@ -6,23 +6,23 @@
  *******************************************************/
 
 
-object \"C_10\" {
+object \"C_11\" {
     code {
         mstore(64, 128)
         if callvalue() { revert(0, 0) }
 
-        constructor_C_10()
+        constructor_C_11()
 
-        codecopy(0, dataoffset(\"C_10_deployed\"), datasize(\"C_10_deployed\"))
+        codecopy(0, dataoffset(\"C_11_deployed\"), datasize(\"C_11_deployed\"))
 
-        return(0, datasize(\"C_10_deployed\"))
+        return(0, datasize(\"C_11_deployed\"))
 
-        function constructor_C_10() {
+        function constructor_C_11() {
 
         }
 
     }
-    object \"C_10_deployed\" {
+    object \"C_11_deployed\" {
         code {
             mstore(64, 128)
 
@@ -36,7 +36,7 @@ object \"C_10\" {
                     // f()
                     if callvalue() { revert(0, 0) }
                     abi_decode_tuple_(4, calldatasize())
-                    let ret_0 :=  fun_f_9()
+                    let ret_0 :=  fun_f_10()
                     let memPos := allocateMemory(0)
                     let memEnd := abi_encode_tuple_t_bytes32__to_t_bytes32__fromStack(memPos , ret_0)
                     return(memPos, sub(memEnd, memPos))
@@ -79,11 +79,11 @@ object \"C_10\" {
                 converted := 0x6162636162630000000000000000000000000000000000000000000000000000
             }
 
-            function fun_f_9() -> vloc__4 {
+            function fun_f_10() -> vloc__5 {
                 let zero_value_for_type_t_bytes32_1 := zero_value_for_split_t_bytes32()
-                vloc__4 := zero_value_for_type_t_bytes32_1
+                vloc__5 := zero_value_for_type_t_bytes32_1
 
-                vloc__4 := convert_t_stringliteral_9f0adad0a59b05d2e04a1373342b10b9eb16c57c164c8a3bfcbf46dccee39a21_to_t_bytes32()
+                vloc__5 := convert_t_stringliteral_9f0adad0a59b05d2e04a1373342b10b9eb16c57c164c8a3bfcbf46dccee39a21_to_t_bytes32()
                 leave
 
             }
diff --git a/test/cmdlineTests/yul_string_format_ascii_bytes32_from_number/input.json b/test/cmdlineTests/yul_string_format_ascii_bytes32_from_number/input.json
index 003dddfa7..fa45bb240 100644
--- a/test/cmdlineTests/yul_string_format_ascii_bytes32_from_number/input.json
+++ b/test/cmdlineTests/yul_string_format_ascii_bytes32_from_number/input.json
@@ -4,7 +4,7 @@
 	{
 		"A":
 		{
-			"content": "//SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; contract C { function f() external pure returns (bytes4) { return 0x61626364; } }"
+			"content": "//SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; pragma abicoder v2; contract C { function f() external pure returns (bytes4) { return 0x61626364; } }"
 		}
 	},
 	"settings":
diff --git a/test/cmdlineTests/yul_string_format_ascii_bytes32_from_number/output.json b/test/cmdlineTests/yul_string_format_ascii_bytes32_from_number/output.json
index 673315c3f..c1d6cfec7 100644
--- a/test/cmdlineTests/yul_string_format_ascii_bytes32_from_number/output.json
+++ b/test/cmdlineTests/yul_string_format_ascii_bytes32_from_number/output.json
@@ -6,23 +6,23 @@
  *******************************************************/
 
 
-object \"C_10\" {
+object \"C_11\" {
     code {
         mstore(64, 128)
         if callvalue() { revert(0, 0) }
 
-        constructor_C_10()
+        constructor_C_11()
 
-        codecopy(0, dataoffset(\"C_10_deployed\"), datasize(\"C_10_deployed\"))
+        codecopy(0, dataoffset(\"C_11_deployed\"), datasize(\"C_11_deployed\"))
 
-        return(0, datasize(\"C_10_deployed\"))
+        return(0, datasize(\"C_11_deployed\"))
 
-        function constructor_C_10() {
+        function constructor_C_11() {
 
         }
 
     }
-    object \"C_10_deployed\" {
+    object \"C_11_deployed\" {
         code {
             mstore(64, 128)
 
@@ -36,7 +36,7 @@ object \"C_10\" {
                     // f()
                     if callvalue() { revert(0, 0) }
                     abi_decode_tuple_(4, calldatasize())
-                    let ret_0 :=  fun_f_9()
+                    let ret_0 :=  fun_f_10()
                     let memPos := allocateMemory(0)
                     let memEnd := abi_encode_tuple_t_bytes4__to_t_bytes4__fromStack(memPos , ret_0)
                     return(memPos, sub(memEnd, memPos))
@@ -83,12 +83,12 @@ object \"C_10\" {
                 converted := shift_left_224(cleanup_t_rational_1633837924_by_1(value))
             }
 
-            function fun_f_9() -> vloc__4 {
+            function fun_f_10() -> vloc__5 {
                 let zero_value_for_type_t_bytes4_1 := zero_value_for_split_t_bytes4()
-                vloc__4 := zero_value_for_type_t_bytes4_1
+                vloc__5 := zero_value_for_type_t_bytes4_1
 
-                let expr_6 := 0x61626364
-                vloc__4 := convert_t_rational_1633837924_by_1_to_t_bytes4(expr_6)
+                let expr_7 := 0x61626364
+                vloc__5 := convert_t_rational_1633837924_by_1_to_t_bytes4(expr_7)
                 leave
 
             }
diff --git a/test/cmdlineTests/yul_string_format_ascii_long/input.json b/test/cmdlineTests/yul_string_format_ascii_long/input.json
index 5d91e402e..b55efa913 100644
--- a/test/cmdlineTests/yul_string_format_ascii_long/input.json
+++ b/test/cmdlineTests/yul_string_format_ascii_long/input.json
@@ -4,7 +4,7 @@
 	{
 		"A":
 		{
-			"content": "//SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; contract C { function f() external pure returns (string memory) { return \"abcdabcdcafecafeabcdabcdcafecafeffffzzzzoooo0123456789,.<,>.?:;'[{]}|`~!@#$%^&*()-_=+\"; } }"
+			"content": "//SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; pragma abicoder v2; contract C { function f() external pure returns (string memory) { return \"abcdabcdcafecafeabcdabcdcafecafeffffzzzzoooo0123456789,.<,>.?:;'[{]}|`~!@#$%^&*()-_=+\"; } }"
 		}
 	},
 	"settings":
diff --git a/test/cmdlineTests/yul_string_format_ascii_long/output.json b/test/cmdlineTests/yul_string_format_ascii_long/output.json
index 3e5052af0..8a1025a46 100644
--- a/test/cmdlineTests/yul_string_format_ascii_long/output.json
+++ b/test/cmdlineTests/yul_string_format_ascii_long/output.json
@@ -6,23 +6,23 @@
  *******************************************************/
 
 
-object \"C_10\" {
+object \"C_11\" {
     code {
         mstore(64, 128)
         if callvalue() { revert(0, 0) }
 
-        constructor_C_10()
+        constructor_C_11()
 
-        codecopy(0, dataoffset(\"C_10_deployed\"), datasize(\"C_10_deployed\"))
+        codecopy(0, dataoffset(\"C_11_deployed\"), datasize(\"C_11_deployed\"))
 
-        return(0, datasize(\"C_10_deployed\"))
+        return(0, datasize(\"C_11_deployed\"))
 
-        function constructor_C_10() {
+        function constructor_C_11() {
 
         }
 
     }
-    object \"C_10_deployed\" {
+    object \"C_11_deployed\" {
         code {
             mstore(64, 128)
 
@@ -36,7 +36,7 @@ object \"C_10\" {
                     // f()
                     if callvalue() { revert(0, 0) }
                     abi_decode_tuple_(4, calldatasize())
-                    let ret_0 :=  fun_f_9()
+                    let ret_0 :=  fun_f_10()
                     let memPos := allocateMemory(0)
                     let memEnd := abi_encode_tuple_t_string_memory_ptr__to_t_string_memory_ptr__fromStack(memPos , ret_0)
                     return(memPos, sub(memEnd, memPos))
@@ -111,11 +111,11 @@ object \"C_10\" {
                 }
             }
 
-            function fun_f_9() -> vloc__4_mpos {
+            function fun_f_10() -> vloc__5_mpos {
                 let zero_value_for_type_t_string_memory_ptr_1_mpos := zero_value_for_split_t_string_memory_ptr()
-                vloc__4_mpos := zero_value_for_type_t_string_memory_ptr_1_mpos
+                vloc__5_mpos := zero_value_for_type_t_string_memory_ptr_1_mpos
 
-                vloc__4_mpos := convert_t_stringliteral_d6604f85ac07e2b33103a620b3d3d75b0473c7214912beded67b9b624d41c571_to_t_string_memory_ptr()
+                vloc__5_mpos := convert_t_stringliteral_d6604f85ac07e2b33103a620b3d3d75b0473c7214912beded67b9b624d41c571_to_t_string_memory_ptr()
                 leave
 
             }
diff --git a/test/cmdlineTests/yul_string_format_hex/input.json b/test/cmdlineTests/yul_string_format_hex/input.json
index 9bb3fd138..51d3dcdff 100644
--- a/test/cmdlineTests/yul_string_format_hex/input.json
+++ b/test/cmdlineTests/yul_string_format_hex/input.json
@@ -4,7 +4,7 @@
 	{
 		"A":
 		{
-			"content": "//SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; contract C { function f() external pure returns (bytes4) { return 0xaabbccdd; } }"
+			"content": "//SPDX-License-Identifier: GPL-3.0\npragma solidity >=0.0; pragma abicoder v2; contract C { function f() external pure returns (bytes4) { return 0xaabbccdd; } }"
 		}
 	},
 	"settings":
diff --git a/test/cmdlineTests/yul_string_format_hex/output.json b/test/cmdlineTests/yul_string_format_hex/output.json
index 9f1ac4b5e..48fca31e8 100644
--- a/test/cmdlineTests/yul_string_format_hex/output.json
+++ b/test/cmdlineTests/yul_string_format_hex/output.json
@@ -6,23 +6,23 @@
  *******************************************************/
 
 
-object \"C_10\" {
+object \"C_11\" {
     code {
         mstore(64, 128)
         if callvalue() { revert(0, 0) }
 
-        constructor_C_10()
+        constructor_C_11()
 
-        codecopy(0, dataoffset(\"C_10_deployed\"), datasize(\"C_10_deployed\"))
+        codecopy(0, dataoffset(\"C_11_deployed\"), datasize(\"C_11_deployed\"))
 
-        return(0, datasize(\"C_10_deployed\"))
+        return(0, datasize(\"C_11_deployed\"))
 
-        function constructor_C_10() {
+        function constructor_C_11() {
 
         }
 
     }
-    object \"C_10_deployed\" {
+    object \"C_11_deployed\" {
         code {
             mstore(64, 128)
 
@@ -36,7 +36,7 @@ object \"C_10\" {
                     // f()
                     if callvalue() { revert(0, 0) }
                     abi_decode_tuple_(4, calldatasize())
-                    let ret_0 :=  fun_f_9()
+                    let ret_0 :=  fun_f_10()
                     let memPos := allocateMemory(0)
                     let memEnd := abi_encode_tuple_t_bytes4__to_t_bytes4__fromStack(memPos , ret_0)
                     return(memPos, sub(memEnd, memPos))
@@ -83,12 +83,12 @@ object \"C_10\" {
                 converted := shift_left_224(cleanup_t_rational_2864434397_by_1(value))
             }
 
-            function fun_f_9() -> vloc__4 {
+            function fun_f_10() -> vloc__5 {
                 let zero_value_for_type_t_bytes4_1 := zero_value_for_split_t_bytes4()
-                vloc__4 := zero_value_for_type_t_bytes4_1
+                vloc__5 := zero_value_for_type_t_bytes4_1
 
-                let expr_6 := 0xaabbccdd
-                vloc__4 := convert_t_rational_2864434397_by_1_to_t_bytes4(expr_6)
+                let expr_7 := 0xaabbccdd
+                vloc__5 := convert_t_rational_2864434397_by_1_to_t_bytes4(expr_7)
                 leave
 
             }
diff --git a/test/cmdlineTests/yul_unimplemented/err b/test/cmdlineTests/yul_unimplemented/err
index 1ce8608a6..d1b862ce2 100644
--- a/test/cmdlineTests/yul_unimplemented/err
+++ b/test/cmdlineTests/yul_unimplemented/err
@@ -1,5 +1,5 @@
 Error (1834): Unimplemented feature error in <FILENAME REMOVED>
- --> yul_unimplemented/input.sol:5:16:
+ --> yul_unimplemented/input.sol:6:16:
   |
-5 |         return type(test).name;
+6 |         return type(test).name;
   |                ^^^^^^^^^^^^^^^
diff --git a/test/cmdlineTests/yul_unimplemented/input.sol b/test/cmdlineTests/yul_unimplemented/input.sol
index eab2109d8..c9ea15c48 100644
--- a/test/cmdlineTests/yul_unimplemented/input.sol
+++ b/test/cmdlineTests/yul_unimplemented/input.sol
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0
 pragma solidity >=0.0;
+pragma abicoder v2;
 contract test {
     function f() public pure returns (string memory) {
         return type(test).name;