[llvm] [llvm-ml] Remove unsafe getCurrentSegmentOnly() call (PR #123355)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,7 @@
+; RUN: not llvm-ml -filetype=s %s /Fo /dev/null 2>&1 | FileCheck %s
+
+; CHECK: :[[# @LINE + 1]]:1: error: expected section directive before 'PROC' directive
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MaskRay wrote:

This is ok, but in most cases we omit spaces beside `+`: `LINE+1`

https://github.com/llvm/llvm-project/pull/123355