[FIX] Implicit declaration of these functions throws warning during build

[krushanbauva]

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Should I declare these functions in a header file and include the header file rather than doing it this way?

P.S.: I used the build script on my linux machine which throws warning

[MatejMecka]

s32 ?

[krushanbauva]

It's the way this function is defined in src/gpacmp4/error.c

Also, you can find "typedef int s32" in src/gpacmp4/gpac/setup.h

[cfsmp3]

I'm merging because I'm tired of seeing those warnings myself, even though I'm not a fan of changing libgpac directly.
It would be a good idea to also send this minor thing to the libgpac maintainers.

[krushanbauva]

Also, I was planning to go through all those warnings one by one and fix them! :)
@cfsmp3 Should I really spend time on it?

[krushanbauva]

@cfsmp3 This issue doesn't arise in gpac library. The function is already declared in a header file gpac/include/gpac/iso639.h which is included in the source code.