Building the benchmarks requires google-benchmark to be installed which is
not the case for most of the build systems. The option now has a tiny
hint what the requirement is and where to get it.
closes#975
Using an external fmt lib should cause the spdlog::spdlog target to have
a dependency on fmt lib - so that a consuming project does not need
to call find_package(fmt) and target_link_libraries(... fmt::fmt).
To this end a new cmake option SPDLOG_FMT_EXTERNAL is introduced which
makes spdlog depend on fmt lib and defines the SPDLOG_FMT_EXTERNAL macro
to avoid using the bundled fmt lib. The value of SPDLOG_FMT_EXTERNAL is
also stored in the installed spdlogConfig.cmake and if it is ON
find_dependency() is used to ensure the fmt::fmt target is imported.
This is needed in order to support usage of this library as a
subdirectory in a parent project. In that situation, prior
to this change, the inclusion of CTest would unconditionally
enable BUILD_TESTING which would then bleed into other parts
of the project.
Also added some comments explaining how this logic works.
The value based on whether spdlog is used as a third-party dependency or
as a standalone project. If spdlog is included through add_subdirectory,
the tests/examples/benchmarsk are disabled by default, and if spdlog is
configured standalone, then they are enabled by default.
Added:
* Release/Debug job for gcc 7 and clang 3.5
* Debug asan gcc 7 job
* Debug tsan gcc 7 job
* Disabled extensions
* Added a spdlog::spdlog alias for tests
Removed:
* Valgrind workaround, the current version is 3.10.1
* install_libcxx
* Makefiles
Fixed:
* examples build
* multisink build
Workarounds:
* gcc7 with tsan and asan needs gold linker, otherwise build
fails becase of unrecognized option '--push-state'
