Print warning for unnamed return parameters and no return statement

test/libsolidity/syntaxTests/abiEncoder/v2_accessing_returned_dynamic_array_with_returndata_support.sol

@@ -10,4 +10,5 @@ contract C {
 // ====
 // EVMVersion: >=byzantium
 // ----
+// Warning 6321: (150-154): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 2072: (166-183): Unused local variable.

test/libsolidity/syntaxTests/controlFlow/storageReturn/default_location.sol

@@ -17,3 +17,4 @@ contract C {
     }
 }
 // ----
+// Warning 6321: (399-407): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/dataLocations/function_return_parameters_with_data_location_fine.sol

@@ -4,3 +4,6 @@ contract C {
     function h() public pure returns(uint[] memory) {}
     function i() external pure returns(uint[] memory) {}
 }
+// ----
+// Warning 6321: (51-64): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (134-147): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/freeFunctions/qualified_struct_access.sol

@@ -4,4 +4,5 @@ contract C {
     struct S { uint x; }
 }
 // ----
+// Warning 6321: (22-26): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // TypeError 3464: (45-46): This variable is of storage pointer type and can be accessed without prior assignment, which would lead to undefined behaviour.

test/libsolidity/syntaxTests/metaTypes/typeOfContract.sol

@@ -4,4 +4,5 @@ contract Test {
     }
 }
 // ----
+// Warning 6321: (54-66): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6133: (78-88): Statement has no effect.

test/libsolidity/syntaxTests/multiVariableDeclaration/multiSingleVariableDeclaration.sol

@@ -4,3 +4,5 @@ contract C {
     a;
   }
 }
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/multiVariableDeclaration/multiVariableDeclarationComplex.sol

@@ -9,3 +9,7 @@ contract C {
   function g() internal pure returns (uint, uint, uint, D.S[20] storage x, uint) { x = x; }
 }
 // ----
+// Warning 6321: (176-180): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (182-186): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (188-192): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (213-217): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/multiVariableDeclaration/multiVariableDeclarationSimple.sol

@@ -10,3 +10,8 @@ contract C {
   function h() internal pure returns (bytes memory, string storage s) { s = s; }
 }
 // ----
+// Warning 6321: (51-55): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (57-61): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (63-67): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (69-73): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (250-262): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/nameAndTypeResolution/018_forward_function_reference.sol

@@ -8,3 +8,5 @@ contract Second {
         if (First(2).fun() == true) return 1;
     }
 }
+// ----
+// Warning 6321: (183-187): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/nameAndTypeResolution/no_effect_statements.sol

@@ -9,6 +9,7 @@ contract test {
     }
 }
 // ----
+// Warning 6321: (83-87): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 6133: (93-94): Statement has no effect.
 // Warning 6133: (98-104): Statement has no effect.
 // Warning 6133: (108-112): Statement has no effect.

test/libsolidity/syntaxTests/parsing/address_payable_function_type.sol

@@ -4,3 +4,5 @@ contract C {
         function (address payable) payable external returns (address payable) h; h;
     }
 }
+// ----
+// Warning 6321: (197-267): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/parsing/if_statement.sol

@@ -4,5 +4,6 @@ contract test {
     }
 }
 // ----
+// Warning 6321: (60-64): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 2072: (109-115): Unused local variable.
 // Warning 2018: (20-128): Function state mutability can be restricted to pure

test/libsolidity/syntaxTests/tryCatch/almost_call_options.sol

@@ -11,4 +11,6 @@ contract C {
 // ====
 // EVMVersion: >=byzantium
 // ----
+// Warning 6321: (73-77): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (79-83): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
 // Warning 2072: (122-134): Unused local variable.

test/libsolidity/syntaxTests/tryCatch/catch_error.sol

@@ -8,4 +8,7 @@ contract C {
     }
 }
 // ====
-// EVMVersion: >=byzantium
+// EVMVersion: >=byzantium
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (52-56): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/catch_error_named.sol

@@ -8,4 +8,7 @@ contract C {
     }
 }
 // ====
-// EVMVersion: >=byzantium
+// EVMVersion: >=byzantium
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (52-56): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/catch_low_level.sol

@@ -8,4 +8,7 @@ contract C {
     }
 }
 // ====
-// EVMVersion: >=byzantium
+// EVMVersion: >=byzantium
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (52-56): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/no_returns.sol

@@ -6,4 +6,7 @@ contract C {
 
         }
     }
-}
+}
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (52-56): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/returns.sol

@@ -8,3 +8,6 @@ contract C {
         }
     }
 }
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (52-56): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/returns_memory.sol

@@ -9,3 +9,6 @@ contract C {
 }
 // ====
 // EVMVersion: >=byzantium
+// ----
+// Warning 6321: (46-59): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (61-65): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/returns_memory_anonymous.sol

@@ -8,4 +8,7 @@ contract C {
     }
 }
 // ====
-// EVMVersion: >=byzantium
+// EVMVersion: >=byzantium
+// ----
+// Warning 6321: (46-59): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (61-65): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tryCatch/two_catch_clauses.sol

@@ -11,4 +11,7 @@ contract C {
     }
 }
 // ====
-// EVMVersion: >=byzantium
+// EVMVersion: >=byzantium
+// ----
+// Warning 6321: (46-50): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (52-56): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/tupleAssignments/large_component_count.sol

@@ -21,3 +21,6 @@ contract C {
 	}
 }
 // ----
+// Warning 6321: (194-198): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (200-204): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.
+// Warning 6321: (206-213): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/types/function_types/selector/local_variable_selector_not_pure.sol

@@ -6,3 +6,5 @@ contract C {
         g.selector;
     }
 }
+// ----
+// Warning 6321: (51-57): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.

test/libsolidity/syntaxTests/viewPureChecker/call_internal_functions_success.sol

@@ -4,3 +4,5 @@ contract C {
     function h() public { h(); g(); f(); }
     function i() payable public { i(); h(); g(); f(); }
 }
+// ----
+// Warning 6321: (89-93): Unnamed return variable can remain unassigned. Add an explicit return with value to all non-reverting code paths or name the variable.