[OpenZL] Overlapping macros

[kevinjzhang]

Internally, OpenZL has portability.h and zl_portability.h which both contain portability macros. These two files share some macros such as ZL_UNUSED or ZL_UNUSED_ATTR. We should clean this up.

[Hanu-man12]

Hi @kevinjzhang, I'd like to work on this issue.

I've looked at the codebase and can see both portability.h
and zl_portability.h contain overlapping macros like
ZL_UNUSED and ZL_UNUSED_ATTR.

My plan would be to:

1. Identify all duplicate macros between the two files
2. Consolidate them into zl_portability.h
3. Update all references to use the single source

Could you confirm this approach before I start?

[kevinjzhang]

@Hanu-man12 sorry about the late response, we really appreciate the interest in working on this! I mostly filed this issue so that we can address this ourselves at some point in the future. There are some other considerations that make it easier for this work to be done internally - especially as it involves a public header (zl_portability.h).