[lld] [LLD][COFF] Require explicit specification of ARM64EC target (PR #116281)

[Jacek Caban via llvm-commits]

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@@ -74,13 +77,18 @@ void SymbolTable::addFile(InputFile *file) {
   }
 
   MachineTypes mt = file->getMachineType();
+  if (!compatibleMachineType(ctx, mt)) {
+    if (isArm64EC(mt))
+      error(toString(file) + ": incompatible machine type " + machineToStr(mt) +
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cjacek wrote:

I’ve improved the error message and its logic. The updated implementation now tracks if the machine type was inferred earlier, as it could have been inferred as ARM64 or AMD64 from prior input files (as demonstrated in the tests). Additionally, I noticed that ARM64X input files are allowed to infer ARM64, so I’ve added support for that behavior as well.

https://github.com/llvm/llvm-project/pull/116281