lime rebuild ios fails on M1 due to multiple architecture flags

[tobil4sk]

By default, when running lime rebuild ios, both armv7 and arm64 architecture flags are active. See:

lime/tools/platforms/IOSPlatform.hx

Lines 478 to 482 in e6205bf

	var armv7 = (command == "rebuild"
	|| (project.architectures.indexOf(Architecture.ARMV7) > -1 && !project.targetFlags.exists("simulator")));
	var armv7s = (project.architectures.indexOf(Architecture.ARMV7S) > -1 && !project.targetFlags.exists("simulator"));
	var arm64 = (command == "rebuild"
	|| (project.architectures.indexOf(Architecture.ARM64) > -1 && !project.targetFlags.exists("simulator")));

This means that HXCPP_ARMV7 and HXCPP_ARM64 are set at once:

lime/tools/platforms/IOSPlatform.hx

Lines 491 to 493 in e6205bf

	if (armv7) commands.push(["-Dios", "-DHXCPP_CPP11", "-DHXCPP_ARMV7"]);
	if (armv7s) commands.push(["-Dios", "-DHXCPP_CPP11", "-DHXCPP_ARMV7S"]);
	if (arm64) commands.push(["-Dios", "-DHXCPP_CPP11", "-DHXCPP_ARM64"]);

The hxcpp code does not allow for these flags to be set at once (see https://github.com/HaxeFoundation/hxcpp/blob/18f87b949464ddcf24c6a83a2f7b8f76233540bc/toolchain/iphoneos-toolchain.xml#L43-L47).

The compiler receives -arch armv7 arm64, so only armv7 is treated as an architecture flag, and the arm64 is treated as a file to be compiled, resulting in the error:

Error: clang: error: no such file or directory: 'arm64'

Perhaps it's fine to just no longer set HXCPP_ARMV7 by default? Considering the commit message here: f34b595.

[player-03]

In IOSPlatform, commands is an array of arrays. Each sub-array is handled independently, meaning the two flags aren't set at once. Your error must be coming from somewhere else.

[tobil4sk]

Each sub-array is handled independently, meaning the two flags aren't set at once.

Ah you're right... So the HXCPP_ARM64 flag is being set from elsewhere. Worth noting that this problem happened when compiling ios from m1.

[tobil4sk]

Maybe the problem is just that the host architecture results in a flag being added, when that should not be happening.

This would go unnoticed on intel mac is because the x86_64 architecture does not result in a -arch flag being set, so even if the host architecture bled through into the compiler flags it wouldn't cause any issues:

https://github.com/HaxeFoundation/hxcpp/blob/18f87b949464ddcf24c6a83a2f7b8f76233540bc/toolchain/iphoneos-toolchain.xml#L43-L47

[tobil4sk]

After further debugging, it looks like the problem lies with hxcpp, not lime: HaxeFoundation/hxcpp#1079