I'm trying to follow the API guide to setup ethminer, but for some reason I keep getting an error when attempting to build the c++ ethereum mining software. The guide I'm trying to follow is: http://www.ethdocs.org/en/latest/ethereum-clients/cpp-ethereum/building-from-source/windows.html
It reads as follows:

C:\Windows\System32\cpp-ethereum\build> cmake -G "Visual Studio 14 2015 Win64" .. CMAKE Error at CMakeLists.txt:44 (project): Failed to run MSBuild command: C:/Program Files (x86)/MSBuild/14.0/bin/MSBuild.exe to get the value of VCTargetsPath: Microsoft (R) Build ENgine version 14.0.25420.1 Copyright (C) Microsoft Corporation. All rights reserved. MSBUILD : error MSB1009: Project file does not exist. Switch: VCTargetsPath.vcxproj Exit code: 1 -- Configuring incomplete, errors occurred! See also "C:/Windows/System32/cpp-ethereum/build/CMakeFiles/CMakeOutput.log". 

The afformentioned log only has this:

The system is: Windows - 10.0.15063 - AMD64 

I have VS2015 installed as well as cmake and git, I'm not sure what I'm doing wrong. Does anyone know what I can do to get around this problem? Thanks!
Included in the build directory is a CMakeCache.txt, which seems to hold the settings for the build, and reads as follow:

# This is the CMakeCache file. # For build in directory: c:/Windows/System32/cpp-ethereum/build # It was generated by CMake: C:/Program Files/CMake/bin/cmake.exe # You can edit this file to change values found and used by cmake. # If you do not want to change any of the values, simply exit the editor. # If you do want to change a value, simply edit, save, and exit the editor. # The syntax for the file is as follows: # KEY:TYPE=VALUE # KEY is the name of a variable in the cache. # TYPE is a hint to GUIs for the type of VALUE, DO NOT EDIT TYPE!. # VALUE is the current value for the KEY. ######################## # EXTERNAL cache entries ######################## //Semicolon separated list of supported configuration types, only // supports Debug, Release, MinSizeRel, and RelWithDebInfo, anything // else will be ignored. CMAKE_CONFIGURATION_TYPES:STRING=Debug;Release;MinSizeRel;RelWithDebInfo //Value Computed by CMake CMAKE_PROJECT_NAME:STATIC=cpp-ethereum //The CMake toolchain file CMAKE_TOOLCHAIN_FILE:FILEPATH=C:/Windows/System32/cpp-ethereum/cmake/toolchain.cmake //Path to the root directory for cpp-ethereum CPP_ETHEREUM_DIR:PATH=C:/Windows/System32/cpp-ethereum //The path to the cmake directory ETH_CMAKE_DIR:PATH=C:/Windows/System32/cpp-ethereum/cmake //Value Computed by CMake cpp-ethereum_BINARY_DIR:STATIC=C:/Windows/System32/cpp-ethereum/build //Value Computed by CMake cpp-ethereum_SOURCE_DIR:STATIC=C:/Windows/System32/cpp-ethereum ######################## # INTERNAL cache entries ######################## //This is the directory where this CMakeCache.txt was created CMAKE_CACHEFILE_DIR:INTERNAL=c:/Windows/System32/cpp-ethereum/build //Major version of cmake used to create the current loaded cache CMAKE_CACHE_MAJOR_VERSION:INTERNAL=3 //Minor version of cmake used to create the current loaded cache CMAKE_CACHE_MINOR_VERSION:INTERNAL=9 //Patch version of cmake used to create the current loaded cache CMAKE_CACHE_PATCH_VERSION:INTERNAL=0 //Path to CMake executable. CMAKE_COMMAND:INTERNAL=C:/Program Files/CMake/bin/cmake.exe //Path to cpack program executable. CMAKE_CPACK_COMMAND:INTERNAL=C:/Program Files/CMake/bin/cpack.exe //Path to ctest program executable. CMAKE_CTEST_COMMAND:INTERNAL=C:/Program Files/CMake/bin/ctest.exe //Name of external makefile project generator. CMAKE_EXTRA_GENERATOR:INTERNAL= //Name of generator. CMAKE_GENERATOR:INTERNAL=Visual Studio 14 2015 Win64 //Name of generator platform. CMAKE_GENERATOR_PLATFORM:INTERNAL= //Name of generator toolset. CMAKE_GENERATOR_TOOLSET:INTERNAL= //Source directory with the top level CMakeLists.txt file for this // project CMAKE_HOME_DIRECTORY:INTERNAL=C:/Windows/System32/cpp-ethereum //number of local generators CMAKE_NUMBER_OF_MAKEFILES:INTERNAL=1 //Platform information initialized CMAKE_PLATFORM_INFO_INITIALIZED:INTERNAL=1 //Path to CMake installation. CMAKE_ROOT:INTERNAL=C:/Program Files/CMake/share/cmake-3.9 

Other than that there really isn't much else... no error logs as far as I can see either

I'm designing a private Ethereum blockchain. Now, I'm choosing which technology is suitable for the project. My customer has concerns with GPLs licenses and I reach this 2 projects which have MIT license. Does anyone use them? I would like to know your experience with them and recommendations.

For instance webthree-umbrella (which includes web3.js as a module): https://github.com/ethereum/webthree-umbrella
Or webthree, which provides eth: https://github.com/ethereum/webthree/tree/develop
Or libwebthreecore, which provides C++ Ethereum "stuff": https://github.com/ethereum/libweb3core/tree/develop
If you look at commit histories, it would seem that the original cpp-ethereum repository is being moved to ones titled "webthree".
This is causing immense confusion for some developers as well as for projects that rely on this code. For instance, the correct answer for "Where can I find the most up to date Solidity compiler?" is no longer obvious -- not to mention that the broad changes made to Solidity, for those that receive versions not available in the cpp-ethereum repository, are causing cascading issues.
That said, the name change is confusing. For instance: Is web3 (aka "webthree") more than just the javascript library for interacting with Ethereum? Does "webthree" now include both the Ethereum library as well as the cpp-ethereum client (but not pyethereum, go-ethereum, ethereumjs, etc.)? If so, why? What's the point of merging these names, which to me are very distinct projects, all under the Ethereum umbrella?
Would love your thoughts. Cheers.
Edit: A word. And this edit update.

Could someone that has successfully installed Cpp-Ethereum on OSX with GPU mining please post a step by step of exactly the install path you took.

https://github.com/ethereum/cpp-ethereum/blob/develop/LICENSE
https://github.com/ethereum/pyethereum/blob/develop/LICENSE
Why is there a difference between the two licenses when they provide the same functionality? I'd be more inclined to use python since it's MIT.

Hey, so I've been mining for the past two weeks almost with no problems. I am using cpp-ethereum and I haven't encountered any problems until today. I went ahead and launched cmd, changed the directory so it could find the executable file, and ran the command line to start the process. But after 3 lines, it crashed. Do you know what could possibly be causing this and how to fix it? Thanks for your help Edit: Thanks for trying to help guys but I fixed it. Just had to delete the dag files in Ethash folder

We just released cpp-ethereum version 1.2.3. release page.
This change further simplifies the codebase and removes some components of eth which were unstable or not well maintainable. These include:

• the built-in javascript console (please use ethconsole instead)
• AlethOne (the "one-click GUI miner") - the idea behind such a project is nice, but the wide range of different GPU hardware and many other factors resulted in AlethOne just not delivering the experience. Please use ethminer on the commandline.

Changelog

• fixed issues where blockchain sync got stuck
• moved lll and libevmasm into solidity repository
• removed the internal javascript console
• implemented eth_pendingTransactions rpc call
• removed compiler rpc calls to simplify dependencies
• improved commandline interface of EVM benchmarking tool (use JIT even when requesting stats)

edit: formatting

Was it also affected?

We just released version 1.2.4 of cpp-ethereum including version 1.0.3 of mix and version 0.3.2 of solidity.
In this release we mainly focused on the build system and changes not visible to the end-user. The aim is to decouple the various binaries so that they can be built in isolation. For Solidity, some quite important bugs were fixed, so please upgrade.
Important: The Mix binary was renamed to mix-ide in order to avoid name conflicts with elixir's build tool.
Changelog
eth (1.2.4):

• removed browser plugin in AlethZero
• support for the Intel compiler on Ubuntu
• support for xcode 7.3 on OS X

solidity (0.3.2):

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

mix (1.0.3):

• rename to mix-ide to avoid conflict with elixir build tools
• bugfix: transaction arguments for unnamed parameters were not saved correctly

Title basically says it all. When I try to cd into it, it says "The system cannot find the path specified."

The newest binary version of solc for windows I could find is one available in cpp-ethereum release. I compiled a contract with it (the version of solc is 0.3.5-5f97274a/RelWithDebInfo-Windows/msvc/Interpreter, but this version is not available on Etherscan to verify a contract with :(. Can it be made available? Or is there any other binary version that can be easily downloaded that is on Etherscan?

Hey there, trying to install the solidity compiler and get started, but I've been running into issues downloading the dependencies from homebrew. Anyone run into this before?

==> Cloning https://github.com/ethereum/cpp-ethereum.git Updating /Users/ryan/Library/Caches/Homebrew/cpp-ethereum--git ==> Checking out branch develop warning: unable to rmdir deps: Directory not empty ==> cmake -DCMAKE_C_FLAGS_RELEASE=-DNDEBUG -DCMAKE_CXX_FLAGS_RELEASE=-DNDEBUG -DCMAKE_INSTALL_PREFIX=/uslocal/Cellacpp-ethereum/1.3.0 -DCMAKE_BUILD_TYPE=Release -DCMAKE_FIND_FRAMEWORK=LAST -DCMAKE_VER Last 15 lines from /Users/ryan/Library/Logs/Homebrew/cpp-ethereum/01.cmake: -- Check for working CXX compiler: /uslocal/Homebrew/Library/Homebrew/shims/supeclang++ -- Check for working CXX compiler: /uslocal/Homebrew/Library/Homebrew/shims/supeclang++ -- works -- Detecting CXX compiler ABI info -- Detecting CXX compiler ABI info - done -- Detecting CXX compile features -- Detecting CXX compile features - done CMake Error at cmake/EthCompilerSettings.cmake:68 (message): This compiler AppleClang 8.1.0.8020042 is not able to compile required libff. Install clang 4+ from Homebrew. Call Stack (most recent call first): CMakeLists.txt:94 (include) -- Configuring incomplete, errors occurred! See also "/tmp/cpp-ethereum-20170904-66078-15y3sg0/CMakeFiles/CMakeOutput.log". If reporting this issue please do so at (not Homebrew/brew or Homebrew/core): https://github.com/ethereum/homebrew-ethereum/issues 

The code is optimized for GTX1060, can improve GTX1060 with 2 GPC performance by 15%, and GTX1060 with 1 GPC performance by more than 30%. Meanwhile, it also increases performance on GTX1070 by 3%, on Telsla M60 by 2%, and should also benefit other chips.
When executing the code, please do remember to add "-U" to your argument. Two locations to download the code:

1. https://github.com/Genoil/cpp-ethereum/pull/228
   
2. https://github.com/ethereum-mining/ethminepull/18
   
3. Windows exe download: https://ci.appveyor.com/project/ethereum-mining/ethminebuild/93/job/ss7k95dsy1kly4vl/artifacts
   

If you have any concerns about the code, don't hesitate to comment or send email to me.
Some detailed information about the optimization:

1. ethash_cuda_miner_kernel.cu I have commented out "launch_bounds" in the code. launch_bound is discussed in http://docs.nvidia.com/cuda/cuda-c-programming-guide/index.html#axzz4fzSzZc9p in detail.
   
2. dagger_shuffle.cuh 1) We moved around and reduced variable definitions to the minimum required. The compiler should have been able to do this analysis, but it never hurts to help out the compiler. The state in compute_hash of dagger_shuffle.cuh is modified. 2) We simplify the nested if/else blocks into a switch statement. 3) We simplify control flow. Remove the conditional from the inner loop so all threads calculate the value, and then all threads use a __shfl to read thread t's value (throwing away the rest of the threads' calculated value). 4) We increase the total number of LDGs to increase occupancy. We define PARALLEL_HASH to let each warp have PARALLEL_HASH LDGs in-flight at a time, not 1 at a time, which is the original case.
   
3. keccak.cuh Since the input argument uint2 *s is changed in dagger_shuffle.cuh, we have to modify keccak_f1600_init and keccak_f1600_final in keccak.cuh accordingly.
   

Thanks to everyone who joined in the live stream. Here are some notes from today's meeting.

Reminder: Metropolis is now split into 2 hard forks: "Byzantium" first and then "Constantinople".

Ice Age Updates

Block times:

• 23 seconds now (block #4200000)
• 30 seconds on Sept. 22nd (block #4300000)
• 39 seconds on Oct. 27th (block #4400000)

EIP 649 Discussion

EIP 649: Metropolis Difficulty Bomb Delay and Issuance Reductio discussion.

• kybarnet kindly joined the call (starting at 9:29) to discuss the issuance reduction and to argue for a further reduction.
• There are others in the community, notably DeviateFish_, who argue that there should be no issuance reduction, but unfortunately they were unable to join the call.
• The conclusion we came to in the call was to keep the issuance reduction for the Byzantium hard fork to 3 ETH in accordance with EIP 649.
• It is unfortunate that certain parties in the discussion (particularly TheCryptoMines) felt left out and I want to find ways in the future to include everyone in the conversation around EIPs and network changes.
• I address this specifically at 1:04:43 and Martin H.S provides good commentary at the end of the discussion.
• It should be noted that changes like this can be reversed or modified in future hard forks with enough community and developer consensus.
• Other posts and opinions from DeviateFish_ and TheCryptoMines can be found here.

Metropolis Testing

• The testing team has grown significantly from 3 people to 7 people (starts at 37:05).
• Big shout out to Dimitry, Casey D., Yoichi, Martin H.S, Tim S., Jared W., Matthew E. who have contributed to the testing efforts!
• Testing is proceeding more smoothly and major clients, including Parity and geth, have implemented most or all of the EIPs that are going into Byzantium.
• cdetrio created an awesome tool for running state tests on multiple clients (starts at 40:41)
• Tim S. (Testing), Arkidiy (Parity), and Martin H.S (Testing) will be working to get the opcode benchmarks necessary to complete gas cost analysis prior to launching Byzantium on the testnet.

Launching the First Part of Metropolis: Byzantium (starts at 56:36)

• Within the next 7-10 days we should have benchmarks for gas costs completed.
• Once the gas costs benchmarks are finalized and the clients complete implementation of the Byzantium EIPs, we will launch a hard fork on the Ropsten testnet that would run for 2-4 weeks.
• Ropsten is hard to sync, so we will look into finding creative ways for people to more easily sync Ropsten. Example: Use lightsync, fastsync, or warpsync, depending on client.
• Block number for the mainnet hard fork will be decided soonish. Ballpark block numbers are : block 4.3 million on Sept. 22nd and worst case is block 4.4 million Oct. 27th, so the hardfork will likely be between those two times. We are aiming for sometime late September.

Clients represented in the meeting

• geth (Go)
• Parity (Rust)
• cpp-ethereum (C++)
• pyethapp (Python)
• ethereumJS (Javascript)
• ethereumJ (Java)

The meeting agenda can be found here and a video of the meeting is here.