From 58cc6cbb379015d57b8f6dec3b4a5c207ccb6b0b Mon Sep 17 00:00:00 2001 From: chriseth Date: Thu, 28 Jul 2016 17:19:17 +0200 Subject: Bugfix: Allocate empty array. --- libsolidity/codegen/CompilerUtils.h | 1 + libsolidity/codegen/ExpressionCompiler.cpp | 9 ++++++--- test/libsolidity/SolidityEndToEndTest.cpp | 14 ++++++++++++++ 3 files changed, 21 insertions(+), 3 deletions(-) diff --git a/libsolidity/codegen/CompilerUtils.h b/libsolidity/codegen/CompilerUtils.h index 55254013..da74dc90 100644 --- a/libsolidity/codegen/CompilerUtils.h +++ b/libsolidity/codegen/CompilerUtils.h @@ -104,6 +104,7 @@ public: ); /// Zero-initialises (the data part of) an already allocated memory array. + /// Length has to be nonzero! /// Stack pre: /// Stack post: void zeroInitialiseMemoryArray(ArrayType const& _type); diff --git a/libsolidity/codegen/ExpressionCompiler.cpp b/libsolidity/codegen/ExpressionCompiler.cpp index b973a117..80009a90 100644 --- a/libsolidity/codegen/ExpressionCompiler.cpp +++ b/libsolidity/codegen/ExpressionCompiler.cpp @@ -792,15 +792,18 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall) utils().storeFreeMemoryPointer(); // Stack: memptr requested_length + // Check if length is zero + m_context << Instruction::DUP1 << Instruction::ISZERO; + auto skipInit = m_context.appendConditionalJump(); + // We only have to initialise if the base type is a not a value type. if (dynamic_cast(arrayType.baseType().get())) { m_context << Instruction::DUP2 << u256(32) << Instruction::ADD; utils().zeroInitialiseMemoryArray(arrayType); - m_context << Instruction::POP; } - else - m_context << Instruction::POP; + m_context << skipInit; + m_context << Instruction::POP; break; } default: diff --git a/test/libsolidity/SolidityEndToEndTest.cpp b/test/libsolidity/SolidityEndToEndTest.cpp index 8dcc878e..4b634649 100644 --- a/test/libsolidity/SolidityEndToEndTest.cpp +++ b/test/libsolidity/SolidityEndToEndTest.cpp @@ -6837,6 +6837,20 @@ BOOST_AUTO_TEST_CASE(skip_dynamic_types_for_structs) BOOST_CHECK(callContractFunction("g()") == encodeArgs(u256(2), u256(6))); } +BOOST_AUTO_TEST_CASE(create_dynamic_array_with_zero_length) +{ + char const* sourceCode = R"( + contract C { + function f() returns (uint) { + var a = new uint[][](0); + return 7; + } + } + )"; + compileAndRun(sourceCode, 0, "C"); + BOOST_CHECK(callContractFunction("f()") == encodeArgs(u256(7))); +} + BOOST_AUTO_TEST_SUITE_END() } -- cgit v1.2.3