Thanks Wes.

From: Wes McKinney <>
Sent: Thursday, June 24, 2021 10:46:01 AM
Subject: Re: LLVM Question
clang-format is only used in development for formatting the codebase (and checking that it's been formatted). Clang tools (format and tidy) aren't necessary for building the library (Gandiva) that requires LLVM

On Thu, Jun 24, 2021 at 9:43 AM Weber, Eugene <> wrote:


I'm running Centos 7. In the Arrow C++ build documentation it states that you are using LLVM 8. I can install llvm-toolset-7.0 which contains llvm/clang version 7.0.1. To get a more recent version of llvm on Centos 7 it would need to be built from source. I tried to do this a few times following various online "recipes", but failed. Not the clearest/simplest process I've seen. 😉 I decided to just give version 7.0.1 a try. 

Attached is my build script and build log. It appears to build successfully, but it does give these messages:

-- clang-tidy not found

-- clang-format not found

-- Could NOT find ClangTools (missing: CLANG_FORMAT_BIN CLANG_TIDY_BIN)

I tried adding the following to my build script: 

export CLANG_TIDY_BIN=/opt/rh/llvm-toolset-7/root/usr/bin

export CLANG_FORMAT_BIN=/opt/rh/llvm-toolset-7.0/root/usr/bin

export PATH=/opt/rh/llvm-toolset-7/root/usr/bin:$PATH

But the messages remain.

When I run unit tests, all 71 tests pass. So at this point there doesn't appear to be any issue using llvm/clang 7.0.1. 

Are the "not found" messages OK?
Is it OK to use llvm/clang 7.0.1?