[PATCH] D83866: [SystemZ/ZOS] Additions to the build system.

Tue Aug 11 05:22:39 PDT 2020

Kai added inline comments.

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Comment at: llvm/CMakeLists.txt:410
+if (CMAKE_SYSTEM_NAME MATCHES "OS390")
+  option(LLVM_ENABLE_PIC "Build Position-Independent Code" OFF)
+else()
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hubert.reinterpretcast wrote:
> Is it actually true that the resulting code is not position-independent? I thought that all XPLINK code is DLL-enabled. The outcome where the resulting code is position-independent (without the need to specify additional options) should be expressed differently from what is done here.
You're right. This is not required.

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Comment at: llvm/cmake/modules/HandleLLVMOptions.cmake:1010
+if(CMAKE_SYSTEM_NAME MATCHES "OS390" AND LLVM_EXPORT_SYMBOLS_FOR_PLUGINS)
+  message(FATAL_ERROR "Generating export from the static libraries is not supported on z/OS")
+endif()
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hubert.reinterpretcast wrote:
> What is the nature of this limitation? "Not supported" messages tend to confuse, because someone wanting to solve the issue (other than not using whatever is "unsupported") needs some rationale in order to make progress.
> 
> Indeed, the text of the message speaks to a limitation to the implementation strategy used by the build and does not directly say much about there being a limitation in achieving the outcome that the option is intended to produce.
I agree that this is text is unclear. I'll deal later with this.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D83866/new/

https://reviews.llvm.org/D83866