kc3-lang/SDL

2020-12-09T06:17:55

Fixed bug 5366 - cmake build doesn't detect Metal on macOS Tom Seddon 2nd time lucky, perhaps. patch 2 applies to current HEAD at time of writing - 4eb049c9bb1ca94efe3c40b57beda3169984d0cb from https://github.com/SDL-mirror/SDL. This basically goes back to what was there originally, but now manually adding "-x objective-c" to the clang command line rather than "-ObjC". clang is then invoked without the "-x c" that was causing the problem, the snippet builds, and Metal is detected. (I had a quick trawl through the cmake code, but I couldn't see where this is handled.) I was moved to try this after finding SDL's own CHECK_OBJC_SOURCE_COMPILES macro, and noting what it does: https://github.com/SDL-mirror/SDL/blob/4eb049c9bb1ca94efe3c40b57beda3169984d0cb/cmake/macros.cmake#L67 An alternative fix of course would be to use CHECK_OBJC_SOURCE_COMPILES instead of cmake's check_objc_source_compiles - but that had the same problem of getting confused by "return 0;". (Maybe that's because it's a macro? I'll defer to a cmake expert on this one.) I decided in the end to err on the side of leaving things looking basically the same as they were before my first patch.