[lld] [LLD] Implement --enable-non-contiguous-regions (PR #90007)

[Fangrui Song via llvm-commits]

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@@ -309,6 +310,12 @@ std::string InputSectionBase::getObjMsg(uint64_t off) const {
       .str();
 }
 
+PotentialSpillSection::PotentialSpillSection(InputSectionBase *source,
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MaskRay wrote:

We prefer `const &`  when a parameter is non-null.

https://github.com/llvm/llvm-project/pull/90007