[llvm] [MC,ELF] Emit warning if a string constant contains newline char. (PR #98060)

[Sergei Barannikov via llvm-commits]

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@@ -0,0 +1,54 @@
+// RUN: llvm-mc -filetype=obj -triple x86_64 %s 2>&1 -o /dev/null | FileCheck -DFILE=%s --strict-whitespace %s --implicit-check-not="{{[0-9]+:[0-9]+: warning: unterminated string}}" --check-prefix=CHECK-WARN
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s-barannikov wrote:


```suggestion
// RUN: llvm-mc -filetype=obj -triple x86_64 %s 2>&1 -o /dev/null \
//   | FileCheck %s --implicit-check-not="{{[0-9]+:[0-9]+: warning: unterminated string}}" --check-prefix=CHECK-WARN
```

-DFILE is unused and --strict-whitespace no longer seems necessary (?)
Long RUN lines can be split into multiple by the backslash character.


https://github.com/llvm/llvm-project/pull/98060