[lld] [LLD, MachO] Default objc_relative_method_lists on MacOS11+/iOS14+ (PR #101360)

[Daniel Bertalan via llvm-commits]

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@@ -125,7 +136,7 @@ CHK_NO_REL-NEXT:		       imp +[MyClass class_method_02]
 .include "objc-macros.s"
 
 .section	__TEXT,__text,regular,pure_instructions
-.build_version macos, 11, 0
+.build_version macos, 10, 0
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BertalanD wrote:

How about changing the "old" target to `10.15` instead? `-data_const` is already the default for that version, so the change to the segment name above wouldn't be needed.

Even if we do say that our generated binaries should run on macOS 10.0 (from 2001!), they won't. Dyld opcodes -- which we use for pre-chained-fixups targets -- were introduced around the 10.9 times.

https://github.com/llvm/llvm-project/pull/101360