MSVC is a little behind, but otherwise we should be able to assume C11
support in all our compilers. The only C99 builds should just be stale
build files. Such consumers are leaving performance on the table, by
using the worse refcounting implementation.
For now, don't require it in public headers. Android's build is still
defaulting to C99, which means requiring C11 will be disruptive. We can
try the public headers after that's fixed.
Update-Note: If the build fails with an error about C11, remove -std=c99
or -std=gnu99 from your build. Refcounting will get faster.
Change-Id: I2ec6f7d7acc026a451851d0c38f60c14bae6b00f
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/52247
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>