Fixed internal error related to ecrecover and ABIEncoderV2.

Author: chriseth

Changelog.md

@@ -9,6 +9,7 @@ Compiler Features:
 
 Bugfixes:
  * ABIEncoderV2: Fix internal error related to bare delegatecall.
+ * ABIEncoderV2: Fix internal error related to ecrecover.
  * ABIEncoderV2: Fix internal error related to mappings as library parameters.
  * Yul: Properly detect name clashes with functions before their declaration.
 

libsolidity/codegen/ExpressionCompiler.cpp

@@ -1967,12 +1967,17 @@ void ExpressionCompiler::appendExternalFunctionCall(
 	// If the function takes arbitrary parameters or is a bare call, copy dynamic length data in place.
 	// Move arguments to memory, will not update the free memory pointer (but will update the memory
 	// pointer on the stack).
+	bool encodeInPlace = _functionType.takesArbitraryParameters() || _functionType.isBareCall();
+	if (_functionType.kind() == FunctionType::Kind::ECRecover)
+		// This would be the only combination of padding and in-place encoding,
+		// but all parameters of ecrecover are value types anyway.
+		encodeInPlace = false;
 	bool encodeForLibraryCall = funKind == FunctionType::Kind::DelegateCall;
 	utils().encodeToMemory(
 		argumentTypes,
 		parameterTypes,
 		_functionType.padArguments(),
-		_functionType.takesArbitraryParameters() || _functionType.isBareCall(),
+		encodeInPlace,
 		encodeForLibraryCall
 	);
 

test/libsolidity/SolidityEndToEndTest.cpp

@@ -2633,6 +2633,25 @@ BOOST_AUTO_TEST_CASE(ecrecover)
 	ABI_CHECK(callContractFunction("a(bytes32,uint8,bytes32,bytes32)", h, v, r, s), encodeArgs(addr));
 }
 
+BOOST_AUTO_TEST_CASE(ecrecover_abiV2)
+{
+	char const* sourceCode = R"(
+		pragma experimental ABIEncoderV2;
+		contract test {
+			function a(bytes32 h, uint8 v, bytes32 r, bytes32 s) public returns (address addr) {
+				return ecrecover(h, v, r, s);
+			}
+		}
+	)";
+	compileAndRun(sourceCode);
+	u256 h("0x18c547e4f7b0f325ad1e56f57e26c745b09a3e503d86e00e5255ff7f715d3d1c");
+	uint8_t v = 28;
+	u256 r("0x73b1693892219d736caba55bdb67216e485557ea6b6af75f37096c9aa6a5a75f");
+	u256 s("0xeeb940b1d03b21e36b0e47e79769f095fe2ab855bd91e3a38756b7d75a9c4549");
+	u160 addr("0xa94f5374fce5edbc8e2a8697c15331677e6ebf0b");
+	ABI_CHECK(callContractFunction("a(bytes32,uint8,bytes32,bytes32)", h, v, r, s), encodeArgs(addr));
+}
+
 BOOST_AUTO_TEST_CASE(inter_contract_calls)
 {
 	char const* sourceCode = R"(