[lld] [LLD][COFF] Use EC symbol table for output DEF file on ARM64X (PR #125531)

[Martin Storsjö via llvm-commits]

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@@ -74,6 +74,10 @@ IMPLIB-EC-NEXT: Symbol: func
 IMPLIB-EC-NEXT: Symbol: __imp_aux_func
 IMPLIB-EC-NEXT: Symbol: #func
 
+RUN: FileCheck --check-prefix=OUT-DEF %s < out.def
+OUT-DEF:      EXPORTS
+OUT-DEF-NEXT:     func @1
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mstorsjo wrote:

Ah, right - this is a case where we only export on the EC side, due to the `-export:` option only applying there. Not entirely obvious, but as long as it technically covers this change, I guess it's fine.

(For practical use, `-output-def` is more commonly used when exports aren't explicitly specified but just exporting all symbols - but for testing I guess this is fine.)

https://github.com/llvm/llvm-project/pull/125531