Take advantage of C++17's `[[maybe_unused]]` if it's available. Also clang supports `__attribute__((unused))` so add that too.

When building with gcc TSan on, and in Debug mode, we see a warning
like:

benchmark/src/timers.cc: In function ‘std::string benchmark::LocalDateTimeString()’:
src/timers.cc:241:15: warning: ‘char* strncat(char*, const char*, size_t)’ output may be truncated copying 108 bytes from a string of length 127 [-Wstringop-truncation]
  241 |   std::strncat(storage, tz_offset, sizeof(storage) - timestamp_len - 1);
      |   ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

While this is essentially a false positive (we never expect
the number of bytes in tz_offset to be too large), the compiler can't
actually tell that.  Shrink the size of tz_offset to a smaller, but still safe
size to eliminate this warning.
Signed-off-by: Chris Lalancette <clalancette@openrobotics.org>

* Implement custom benchmark name

The benchmark's name can be changed using the Name() function
which internally uses SetName().

* Update AUTHORS and CONTRIBUTORS

* Describe new feature in README

* Move new name function up

Fixes #1106

* Removing conanfile (and support) per #1088

Unclear why this is failing so disabling for now. bazel build still works locally so this is a bazelisk/github workflow thing.

Signed-off-by: SSE4 <tomskside@gmail.com>

Lacks CMake support, see https://github.com/google/benchmark/pull/1090

This reverts commit d8254bb9.

* Create workflow to exercise bazel build

Fixes google#1077

Bazel clients currently cannot build the benchmark library in Release
mode. This commit adds a new target ":benchmark_release" to enable this.

Fixes #1075.

* Add an option to report in seconds.

* Reduce the time of the test.

* Add CSV/JSON tests for new time reports.

The existing behavior results in the `0` value being added twice. Since
`lo` is always added to `dst`, we never want to explicitly add `0` if
`lo` is equal to `0`.

* Adding test for defined names in test fixtures

* include/benchmark/benchmark.h: Added support for macro expansion in benchmark names

* packages versions updated to be in sync with modern python versions

* Rename 'mftbl' to 'mftb'

* Add my name to the contributor list

* z/OS does not support nanosleep, add workaround to use sleep() and usleep() instead

* change unsigned to int, and fix while loop

On s390 architecture, z/OS XL compiler uses HLASM inline assembly, which has different syntax and needs to be distinguished to avoid compilation error.

Noticed missing header when was building llvm with gcc-11:

```
llvm-project/llvm/utils/benchmark/src/benchmark_register.h:17:30:
  error: 'numeric_limits' is not a member of 'std'
   17 |   static const T kmax = std::numeric_limits<T>::max();
      |                              ^~~~~~~~~~~~~~
```

Without this commit, compilation fails on DragonFly with the following message:

```
/home/mneumann/Dev/benchmark.old/src/sysinfo.cc:446:2: error: #warning "HOST_NAME_MAX not defined. using 64" [-Werror=cpp]
^~~~~~~
```

Also note that the sysctl is actually `hw.tsc_frequency` on DragonFly:

```
$ sysctl hw.tsc_frequency
hw.tsc_frequency: 3498984022
```

Tested on:

```
$ uname -a
DragonFly box.localnet 5.9-DEVELOPMENT DragonFly v5.9.0.742.g4b29dd-DEVELOPMENT #5: Tue Aug 18 00:21:31 CEST 2020
```

As per discussions in here [1], LLVM is going to get backend support on
Motorola 68000 series CPUs (a.k.a M68K or M680x0). So it's necessary to
add CycleTimer implementation here, which is simply using `gettimeofday`
same as MIPS. This fixes #1049

[1] https://reviews.llvm.org/D88389

NOTE: This is a fresh-start of #738  pull-request which I messed up by re-editing the commiter email which I forgot to modify before pushing. Sorry for the inconvenience.

This PR brings proposed solution for functionality described in #737 

Fixes #737.

Signed-off-by: Vitaly Zaitsev <vitaly@easycoding.org>

* Fix setup.py and reformat

* Bind benchmark

* Add benchmark option to Python

* Add Python examples for range, complexity, and thread

* Remove invalid multithreading in Python

* Bump Python bindings version to 0.2.0
Co-authored-by: Dominic Hamon <dominichamon@users.noreply.github.com>

* Initial version to try to run python bindings example

* python indent issue in setup.py

* better naming

* Bind Counter to Python

* Bind State methods to Python

* Bind state.counters to Python

* Import _benchmark.Counter

* Add Python example of state usage
Co-authored-by: Dominic Hamon <dominichamon@users.noreply.github.com>

* Create pylint.yml

* improve file matching

* fix some pylint issues

* run on PR and push (force on master only)

* more pylint fixes

* suppress noisy exit code and filter to fatals

* add conan as a dep so the module is importable

* fix lint error on unreachable branch

Revert previous linker additions for FreeBSD as the problem is Bazel using /usr/bin/clang instead of /usr/bin/clang++ to link C++ code. (#1035)

* Adds -lm linker flag for (Free|Open)BSD and uses github.com/bazelbuild/platforms for platform detection.

* Prefer selects.with_or to select the linkopts.

* @platforms appears to be implicitly available. @bazel_skylib would require updating every dependent repository.

* Re-enable platforms package.

Fixes #974. The `cxx_feature_check` now has an additional
optional argument which can be used to supply extra cmake flags
to pass to the `try_compile` command. The `CMAKE_CXX_STANDARD=14`
flag was determined to be the minimum flag necessary to correctly
compile and run the regex feature checks when compiling with Clang
under Windows (n.b. this does *not* refer to clang-cl, the frontend
to the MSVC compiler). The additional flag is not enabled for any
other compiler/platform tuple.

* Add CartesianProduct with associated test

* Use CartesianProduct in Ranges to avoid code duplication
* Add new cartesian_product_test to CMakeLists.txt
* Update AUTHORS & CONTRIBUTORS

* Rename CartesianProduct to ArgsProduct

* Rename test & fixture accordingly
* Add example for ArgsProduct to README

* ctest is now working

* Update README

* remove commented out lines

* Tweaked docs

Added note to use parallel and cleaned build config notes

* Response to comments

* revert all but the readme

* make error message clearer

* drop --parallel