Karl Schultz

- `a18util.c` had a somewhat harmless coding error that can generate a warning. - Add a `.gitignore` file so that git does not track the generated executable.

A pointer to this variable is used in a call to `memory::RegisterCopyStorageBufferBenchmark()`. https://github.com/google/uVkCompute/blob/2e4c8e4c7f871aa5496518fd0ec746f5d80f6051/benchmarks/memory/copy_storage_buffer_main.cc#L41-L44 Since this is a local automatic variable, it goes out of scope and the pointer used to...