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

[Fangrui Song 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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MaskRay wrote:

Agreed. Should just fix the test.

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