[Lldb-commits] [compiler-rt] [libcxx] [libcxxabi] [libunwind] [lldb] [llvm] [compiler-rt] Disable LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON on AIX. (PR #131200)

[Daniel Chen via lldb-commits]

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@@ -223,6 +223,13 @@ endif()
 # This can be used to detect whether we're in the runtimes build.
 set(LLVM_RUNTIMES_BUILD ON)
 
+if (LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND UNIX AND ${CMAKE_SYSTEM_NAME} MATCHES "AIX")
+  # Set LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF as AIX doesn't support it
+  message(WARNING
+  "LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON is not supported on AIX. LLVM_ENABLE_PER_TARGET_RUNTIME_DIR is set to OFF.")
+  set(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR OFF CACHE BOOL "" FORCE)
+endif()
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DanielCChen wrote:

We consider it as recoverable mis-config. Because the driver and the cmake are consistent regarding where to search and output the library, users shouldn't be surprised as the compile/linking/execution should be all working. The only thing that may surprise users is that if they search for the library and find out it is not in the `lib/${triple}` path when they have the option ON. For that, we have the warning message in the build.log to explain why.

My first attempt actually followed what APPLE does: check `if (LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)` at a few places to neglect the option. I later adopted @arichardson suggestion to put the check at one central place.

https://github.com/llvm/llvm-project/pull/131200