[llvm] Warn on align directive with non-zero fill value in virtual sections (PR #66792)

[Luís Marques via llvm-commits]

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@@ -12,5 +12,8 @@
 # CHECK: {{.*}}.s:[[#@LINE+1]]:3: error: SHT_NOBITS section '.bss' cannot have instructions
   addb %al,(%rax)
 
+# CHECK: {{.*}}.s:[[#@LINE+1]]:11: warning: ignoring non-zero fill value in SHT_NOBITS section '.bss'
+.align 4, 42
+
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luismarques wrote:

I added a RUN with `--fatal-warnings`. Let me know if it addresses your concerns properly.

https://github.com/llvm/llvm-project/pull/66792