[llvm] [llvm][ELF]Add Shdr check for getBuildID(#126418) (PR #126537)

[Ruoyu Qiu via llvm-commits]

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@@ -660,7 +660,7 @@ class Elf_Note_Impl {
 
   /// Get the note's descriptor.
   ArrayRef<uint8_t> getDesc(size_t Align) const {
-    if (!Nhdr.n_descsz)
+    if (!Nhdr.n_descsz || !Align)
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cabbaken wrote:

`test/DebugInfo/symbolize-build-id.test` will fail without this check. I'm not sure if I should do the check here, but I think it's valid to add a check here.

https://github.com/llvm/llvm-project/pull/126537