Select OS target as a odin compiler flag

[jansen44]

I just started exploring Odin and the learn_metal examples, but there was a problem related to Metal version:

error: 'id' attribute requires Metal language standard macos-metal2.0 or higher;

I tried searching for any flag related to this matter but Odin had none. So I tried compiling Odin with -mmacosx-version-min=12.0 since Odin was compiling the learn_metal example targeting min MacOS version 10.12 (which used metal1). Even with the flag set on Odin's build_odin.sh file, it could not run properly. I found out that in src/main.cpp there was this condition:

if (build_context.metrics.os == TargetOs_darwin) {
  if (build_context.metrics.arch == TargetArch_arm64) {
	  link_settings = gb_string_appendc(link_settings, " -mmacosx-version-min=12.0.0  ");
  } else {
	  link_settings = gb_string_appendc(link_settings, " -mmacosx-version-min=10.12.0 ");
  }
  link_settings = gb_string_appendc(link_settings, " -e _main ");
}

The problem with it is that even Macbooks like mine (Macbook Pro 2020 - Macos 12.3.1) would target MacOs min version of 10.12, just because it's not Arm based. After changing the condition to target 12.0, every other example ran smoothly.

My suggestion: Add flags to control which OS version the compiler should target.

Example:

odin run . --target=macos12.0

The idea is very raw, but the problem is real. So I guess that after putting some think on it, there may be a good syntax for this flag. This idea is also important because it can influence not only MacOS, but even other OS's.

[jansen44]

So, there is a command for specifying the target, but not the VERSION. This macos12.0 problem is due to de darwin-target version and not the target itself.

I still wish there'd be a flag to determine the version instead of changing the src/main.cpp file everytime :/

[Kelimion]

It's certainly an idea to add a -target-version flag or something of that nature. Does -extra-linker-flags:<string> do anything for you?

[jceipek]

@Kelimion I'm having this problem as well, and -extra-linker-flags does not seem to work to configure this (at least -extra-linker-flags:"-mmacosx-version-min=12.0.0" doesn't work). This is not just important for Metal but also for more basic features. For example, opening a window doesn't cause the window to obey the system dark mode settings unless there's a newer MacOS SDK version specified.

I think -target-version or something similar would be a nice addition to avoid having to recompile the compiler.

[Kelimion]

I've added the following, which will be merged shortly:

-minimum-os-version:<string>
    Sets the minimum OS version targeted by the application
    e.g. -minimum-os-version:12.0.0
    (Only used when target is Darwin)