By default, the project() CMake command defaults to C and C++. [1]
Therefore, CMake might perform tests for both C and C++ compilers as
part of the configuration phase.
However, this has the consequence of the configuration phase to fail if
the system does not have a C++ toolchain installed, even if C++ is not
really used by the top-level project under the default settings.
Some configurations might still require a C++ toolchain, so
enable_language is selectively called under such circumstances.
[1]: https://cmake.org/cmake/help/latest/command/project.html
Import WAMR Fast JIT which is a lightweight JIT with quick startup, small footprint,
relatively good performance (~40% to ~50% of LLVM JIT) and good portability.
Platforms supported: Linux, MacOS and Linux SGX.
Arch supported: x86-64.
