I wanted to know about the reasons Apple dropped the support for “arm” target in its ld64. After searching in the sourcecode I found out that ld64 supports armv4 armv5 armv6 armv7 and its subtypes. The code shows that -force_cpusubtype_ALL for ARM targets is no more supported in “src/ld/options.cpp”) and static const ARMSubType ARMSubTypes doesn’t include “arm” as a possible subtype. My question is whether this behavior is required by LLVM, which does not support an unspecific ARM target or it’s Apple decision to remove it in order to remove support from older devices.
Your best bet would be to ask on the apple developer forums.