[lld] [lld][ELF] Demote symbols in discarded sections to Undefined. (PR #68777)

[Fangrui Song via llvm-commits]

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@@ -4,9 +4,32 @@
 # RUN: rm -rf %t && split-file %s %t && cd %t
 # RUN: llvm-mc -filetype=obj -triple=x86_64 a.s -o a.o
 # RUN: llvm-mc -filetype=obj -triple=x86_64 b.s -o b.o
-# RUN: ld.lld -T a.lds a.o b.o -z undefs -o /dev/null 2>&1 | count 0
-# RUN: ld.lld -T a.lds a.o b.o -o /dev/null 2>&1 | count 0
-# RUN: ld.lld -r -T a.lds a.o b.o -o /dev/null 2>&1 | count 0
+# RUN: not ld.lld --threads=1 -T a.lds a.o b.o -z undefs -o /dev/null 2>&1 | FileCheck %s --check-prefix=SECTION --implicit-check-not=error:
+# RUN: not ld.lld --threads=1 -T a.lds a.o b.o -o /dev/null 2>&1 | FileCheck %s --check-prefixes=SECTION,SYMBOL --implicit-check-not=error:
+# RUN: ld.lld -r -T a.lds a.o b.o -o /dev/null 2>&1 | FileCheck %s --check-prefix=WARNING --implicit-check-not=error:
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MaskRay wrote:

`--implicit-check-not=warning:`

exit code 0 means that there cannot be any error.

https://github.com/llvm/llvm-project/pull/68777