Compiler projects using llvm
# Platform Specific Build Instructions

## Building with GCC

When the library is built using GCC it is necessary to link with the pthread
library due to how GCC implements `std::thread`. Failing to link to pthread will
lead to runtime exceptions (unless you're using libc++), not linker errors. See
[issue #67]https://github.com/google/benchmark/issues/67 for more details. You
can link to pthread by adding `-pthread` to your linker command. Note, you can
also use `-lpthread`, but there are potential issues with ordering of command
line parameters if you use that.

On QNX, the pthread library is part of libc and usually included automatically
(see
[`pthread_create()`]https://www.qnx.com/developers/docs/7.1/index.html#com.qnx.doc.neutrino.lib_ref/topic/p/pthread_create.html).
There's no separate pthread library to link.

## Building with Visual Studio 2015 or 2017

The `shlwapi` library (`-lshlwapi`) is required to support a call to `CPUInfo` which reads the registry. Either add `shlwapi.lib` under `[ Configuration Properties > Linker > Input ]`, or use the following:

```
// Alternatively, can add libraries using linker options.
#ifdef _WIN32
#pragma comment ( lib, "Shlwapi.lib" )
#ifdef _DEBUG
#pragma comment ( lib, "benchmarkd.lib" )
#else
#pragma comment ( lib, "benchmark.lib" )
#endif
#endif
```

Can also use the graphical version of CMake:
* Open `CMake GUI`.
* Under `Where to build the binaries`, same path as source plus `build`.
* Under `CMAKE_INSTALL_PREFIX`, same path as source plus `install`.
* Click `Configure`, `Generate`, `Open Project`.
* If build fails, try deleting entire directory and starting again, or unticking options to build less.

## Building with Intel 2015 Update 1 or Intel System Studio Update 4

See instructions for building with Visual Studio. Once built, right click on the solution and change the build to Intel.

## Building on Solaris

If you're running benchmarks on solaris, you'll want the kstat library linked in
too (`-lkstat`).