[clang] [clang-sycl-linker] Add support for linking static archives (PR #201253)

[Nick Sarnie via cfe-commits]

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@@ -341,6 +342,38 @@ static Expected<LinkResult> linkInputs(ArrayRef<std::string> InputFiles,
 
   // Link in library files.
   for (auto &File : *BCLibFiles) {
+    // Static archives are unpacked and each bitcode member is linked
+    // individually with LinkOnlyNeeded.
+    StringRef Ext = sys::path::extension(File);
+    if (Ext == ".a" || Ext == ".lib") {
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sarnex wrote:

instead of checking the ext should we use `llvm::identify_magic`?

https://github.com/llvm/llvm-project/pull/201253