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Author: redstar

llvm/CMakeLists.txt

@@ -1264,7 +1264,7 @@ endif()
 # Build with _XOPEN_SOURCE on z/OS.
 if (CMAKE_SYSTEM_NAME MATCHES "OS390")
   add_compile_definitions(_XOPEN_SOURCE=600)
-  add_compile_definitions(_XPLATFORM_SOURCE)
+  add_compile_definitions(_XPLATFORM_SOURCE) # Needed e.g. for O_CLOEXEC.
   add_compile_definitions(_OPEN_SYS) # Needed for process information.
   add_compile_definitions(_OPEN_SYS_FILE_EXT) # Needed for EBCDIC I/O.
   add_compile_definitions(_EXT) # Needed for file data.