[llvm] Add -lpthread for powerpc64le shared libs build (PR #132265)

[Sam James via llvm-commits]

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@@ -1320,6 +1320,13 @@ if(LLVM_LINK_LLVM_DYLIB AND LLVM_EXPORT_SYMBOLS_FOR_PLUGINS)
   message(FATAL_ERROR "LLVM_LINK_LLVM_DYLIB not compatible with LLVM_EXPORT_SYMBOLS_FOR_PLUGINS")
 endif()
 
+#The shared libs build for Linux on PowerPC requires -lpthread
+if(BUILD_SHARED_LIBS AND ${CMAKE_SYSTEM_NAME} MATCHES "Linux" AND LLVM_HOST_TRIPLE MATCHES "powerpc*")
+    append("-lpthread"
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thesamesam wrote:

You want to add a dependency on `Threads::Threads` instead.

https://github.com/llvm/llvm-project/pull/132265