Remove winbase.h include.

Add testing for c99 and c11.

Fix the c11 build on linux by using the newer timespec_get function.

On second thought gold doesn't work on linux travis so don't do this.

Add LTO options for linux/macOs too.

Keep symbols during whole program optimization (WPO). ...

This commit just uses the `__pragma(comment(linker, "symbol"));` trick
to ensure that the symbol is kept even if whole program optimization
comes along and tries to remove it.

Fixes #31.

Add support for doing type checks on pointers and also a lovely little hack of doing the typeof the input type + 0 to get around being able to compare a value against a static c-style array.

Try and fix the build failures.

Support the type printer for C11 compilers ...

`_Generic` allows us to select the value based on the type of the
expression, which means we don't need to support function overloading,
and means failing expressions print properly in gcc

Disable warnings about generated spectre mitigations ...

On newer versions of MSVC, the compiler warns at `/Wall` if it will
generate a FENCE to mitigate against spectre

https://docs.microsoft.com/en-us/cpp/error-messages/compiler-warnings/c5045?view=vs-2019

This breaks testing, and is uninteresting for our purposes.

Check that including stdint.h works, because we don't include it on MSVC and it was failing previously.

Use c89 mode for gcc/clang.

MR: CMake fails if you use clang for c and gcc for c++.

Heyo, gaia?