[llvm-dev] [RFC] Strategies for Bootstrapping Compiler-RT builtins

[Chris Bieneman via llvm-dev]

> On Nov 2, 2015, at 9:47 AM, Rowan, Jim <jmr at codeaurora.org> wrote:
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> On Nov 2, 2015, at 11:10 AM, Chris Bieneman via llvm-dev <llvm-dev at lists.llvm.org> wrote:
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>> Today building this toolchain with CMake is impossible because you cannot configure the cross-compiled builtins. The failure is a result of CMake’s try_compile function always testing a full compile then link operation. When bootstrapping a cross-compiler this will always fail because linking even the simplest applications fails when you don’t have libclang_rt prebuilt.
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> Are there side-effects from try_compile that we need?  Can we disable it?

We use try_compile to determine the capabilities of the toolchain you are building with. It is very important that we be able to make these calls in some form to figure out supported compiler flags, architectures, etc…

-Chris

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> Jim Rowan
> jmr at codeaurora.org
> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by the Linux Foundation
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