solidity/Changelog.md

0.4.0 (2016-09-08)

This release deliberately breaks backwards compatibility mostly to enforce some safety features. The most important change is that you have to explicitly specify if functions can receive ether via the payable modifier. Furthermore, more situations cause exceptions to be thrown.

Minimal changes to be made for upgrade:

• Add payable to all functions that want to receive Ether (including the constructor and the fallback function).
• Change _ to _; in modifiers.
• Add version pragma to each file: pragma solidity ^0.4.0;

Breaking Changes:

• Source files have to specify the compiler version they are compatible with using e.g. pragma solidity ^0.4.0; or pragma solidity >=0.4.0 <0.4.8;
• Functions that want to receive Ether have to specify the new payable modifier (otherwise they throw).
• Contracts that want to receive Ether with a plain "send" have to implement a fallback function with the payable modifier. Contracts now throw if no payable fallback function is defined and no function matches the signature.
• Failing contract creation through "new" throws.
• Division / modulus by zero throws.
• Function call throws if target contract does not have code
• Modifiers are required to contain _ (use if (false) _ as a workaround if needed).
• Modifiers: return does not skip part in modifier after _.
• Placeholder statement _ in modifier now requires explicit ;.
• ecrecover now returns zero if the input is malformed (it previously returned garbage).
• The constant keyword cannot be used for constructors or the fallback function.
• Removed --interface (Solidity interface) output option
• JSON AST: General cleanup, renamed many nodes to match their C++ names.
• JSON output: srcmap-runtime renamed to srcmapRuntime.
• Moved (and reworked) standard library contracts from inside the compiler to github.com/ethereum/solidity/std (import "std"; or import owned; do not work anymore).
• Confusing and undocumented keyword after was removed.
• New reserved words: abstract, hex, interface, payable, pure, static, view.

Features:

• Hexadecimal string literals: hex"ab1248fe"
• Internal: Inline assembly usable by the code generator.
• Commandline interface: Using - as filename allows reading from stdin.
• Interface JSON: Fallback function is now part of the ABI.
• Interface: Version string now semver compatible.
• Code generator: Do not provide "new account gas" if we know the called account exists.

Bugfixes:

• JSON AST: Nodes were added at wrong parent
• Why3 translator: Crash fix for exponentiation
• Commandline Interface: linking libraries with underscores in their name.
• Type Checker: Fallback function cannot return data anymore.
• Code Generator: Fix crash when sha3() was used on unsupported types.
• Code Generator: Manually set gas stipend for .send(0).

Lots of changes to the documentation mainly by voluntary external contributors.

0.3.6 (2016-08-10)

Features:

• Formal verification: Take external effects on a contract into account.
• Type Checker: Warning about unused return value of low-level calls and send.
• Output: Source location and node id as part of AST output
• Output: Source location mappings for bytecode
• Output: Formal verification as part of json compiler output.

Bugfixes:

• Commandline Interface: Do not crash if input is taken from stdin.
• Scanner: Correctly support unicode escape codes in strings.
• JSON output: Fix error about relative / absolute source file names.
• JSON output: Fix error about invalid utf8 strings.
• Code Generator: Dynamic allocation of empty array caused infinite loop.
• Code Generator: Correctly calculate gas requirements for memcpy precompile.
• Optimizer: Clear known state if two code paths are joined.

0.3.5 (2016-06-10)

Features:

• Context-dependent path remappings (different modules can use the same library in different versions)

Bugfixes:

• Type Checking: Dynamic return types were removed when fetching data from external calls, now they are replaced by an "unusable" type.
• Type Checking: Overrides by constructors were considered making a function non-abstract.

0.3.4 (2016-05-31)

No change outside documentation.

0.3.3 (2016-05-27)

• Allow internal library functions to be called (by "inlining")
• Fractional/rational constants (only usable with fixed point types, which are still in progress)
• Inline assembly has access to internal functions (as jump labels)
• Running solc without arguments on a terminal will print help.
• Bugfix: Remove some non-determinism in code generation.
• Bugfix: Corrected usage of not / bnot / iszero in inline assembly
• Bugfix: Correctly clean bytesNN types before comparison

0.3.2 (2016-04-18)

• Bugfix: Inline assembly parser: byte opcode was unusable
• Bugfix: Error reporting: tokens for variably-sized types were not converted to string properly
• Bugfix: Dynamic arrays of structs were not deleted correctly.
• Bugfix: Static arrays in constructor parameter list were not decoded correctly.

0.3.1 (2016-03-31)

• Inline assembly
• Bugfix: Code generation: array access with narrow types did not clean higher order bits
• Bugfix: Error reporting: error reporting with unknown source location caused a crash

0.3.0 (2016-03-11)

BREAKING CHANGES:

• Added new keywords assembly, foreign, fixed, ufixed, fixedNxM, ufixedNxM (for various values of M and N), timestamp
• Number constant division does not round to integer, but to a fixed point type (e.g. 1 / 2 != 1, but 1 / 2 == 0.5).
• Library calls now default to use DELEGATECALL (e.g. called library functions see the same value as the calling function for msg.value and msg.sender).
• <address>.delegatecall as a low-level calling interface

Bugfixes:

• Fixed a bug in the optimizer that resulted in comparisons being wrong.

0.2.2 (2016-02-17)

• Index access for types bytes1, ..., bytes32 (only read access for now).
• Bugfix: Type checker crash for wrong number of base constructor parameters.

0.2.1 (2016-01-30)

• Inline arrays, i.e. var y = [1,x,f()]; if there is a common type for 1, x and f(). Note that the result is always a fixed-length memory array and conversion to dynamic-length memory arrays is not yet possible.
• Import similar to ECMAScript6 import (import "abc.sol" as d and import {x, y} from "abc.sol").
• Commandline compiler solc automatically resolves missing imports and allows for "include directories".
• Conditional: x ? y : z
• Bugfix: Fixed several bugs where the optimizer generated invalid code.
• Bugfix: Enums and structs were not accessible to other contracts.
• Bugfix: Fixed segfault connected to function paramater types, appeared during gas estimation.
• Bugfix: Type checker crash for wrong number of base constructor parameters.
• Bugfix: Allow function overloads with different array types.
• Bugfix: Allow assignments of type (x) = 7.
• Bugfix: Type uint176 was not available.
• Bugfix: Fixed crash during type checking concerning constructor calls.
• Bugfix: Fixed crash during code generation concerning invalid accessors for struct types.
• Bugfix: Fixed crash during code generating concerning computing a hash of a struct type.

0.2.0 (2015-12-02)

• Breaking Change: new ContractName.value(10)() has to be written as (new ContractName).value(10)()
• Added selfdestruct as an alias for suicide.
• Allocation of memory arrays using new.
• Binding library functions to types via using x for y
• addmod and mulmod (modular addition and modular multiplication with arbitrary intermediate precision)
• Bugfix: Constructor arguments of fixed array type were not read correctly.
• Bugfix: Memory allocation of structs containing arrays or strings.
• Bugfix: Data location for explicit memory parameters in libraries was set to storage.

0.1.7 (2015-11-17)

• Improved error messages for unexpected tokens.
• Proof-of-concept transcompilation to why3 for formal verification of contracts.
• Bugfix: Arrays (also strings) as indexed parameters of events.
• Bugfix: Writing to elements of bytes or string overwrite others.
• Bugfix: "Successor block not found" on Windows.
• Bugfix: Using string literals in tuples.
• Bugfix: Cope with invalid commit hash in version for libraries.
• Bugfix: Some test framework fixes on windows.

0.1.6 (2015-10-16)

• .push() for dynamic storage arrays.
• Tuple expressions ((1,2,3) or return (1,2,3);)
• Declaration and assignment of multiple variables (var (x,y,) = (1,2,3,4,5); or var (x,y) = f();)
• Destructuring assignment ((x,y,) = (1,2,3))
• Bugfix: Internal error about usage of library function with invalid types.
• Bugfix: Correctly parse Library.structType a at statement level.
• Bugfix: Correctly report source locations of parenthesized expressions (as part of "tuple" story).

0.1.5 (2015-10-07)

• Breaking change in storage encoding: Encode short byte arrays and strings together with their length in storage.
• Report warnings
• Allow storage reference types for public library functions.
• Access to types declared in other contracts and libraries via ..
• Version stamp at beginning of runtime bytecode of libraries.
• Bugfix: Problem with initialized string state variables and dynamic data in constructor.
• Bugfix: Resolve dependencies concerning new automatically.
• Bugfix: Allow four indexed arguments for anonymous events.
• Bugfix: Detect too large integer constants in functions that accept arbitrary parameters.

0.1.4 (2015-09-30)

• Bugfix: Returning fixed-size arrays.
• Bugfix: combined-json output of solc.
• Bugfix: Accessing fixed-size array return values.
• Bugfix: Disallow assignment from literal strings to storage pointers.
• Refactoring: Move type checking into its own module.

0.1.3 (2015-09-25)

• throw statement.
• Libraries that contain functions which are called via CALLCODE.
• Linker stage for compiler to insert other contract's addresses (used for libraries).
• Compiler option to output runtime part of contracts.
• Compile-time out of bounds check for access to fixed-size arrays by integer constants.
• Version string includes libevmasm/libethereum's version (contains the optimizer).
• Bugfix: Accessors for constant public state variables.
• Bugfix: Propagate exceptions in clone contracts.
• Bugfix: Empty single-line comments are now treated properly.
• Bugfix: Properly check the number of indexed arguments for events.
• Bugfix: Strings in struct constructors.

0.1.2 (2015-08-20)

• Improved commandline interface.
• Explicit conversion between bytes and string.
• Bugfix: Value transfer used in clone contracts.
• Bugfix: Problem with strings as mapping keys.
• Bugfix: Prevent usage of some operators.

0.1.1 (2015-08-04)

• Strings can be used as mapping keys.
• Clone contracts.
• Mapping members are skipped for structs in memory.
• Use only a single stack slot for storage references.
• Improved error message for wrong argument count. (#2456)
• Bugfix: Fix comparison between bytesXX types. (#2087)
• Bugfix: Do not allow floats for integer literals. (#2078)
• Bugfix: Some problem with many local variables. (#2478)
• Bugfix: Correctly initialise string and bytes state variables.
• Bugfix: Correctly compute gas requirements for callcode.

0.1.0 (2015-07-10)