[flang] [llvm] [Premerge] Add flang-rt (PR #128678)

[Aiden Grossman via llvm-commits]

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+#!/usr/bin/env bash
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boomanaiden154 wrote:

Makes sense.

Although `-gmlt` is very much not a google-specific extension. These containers run the latest release clang built from source straight from the release branch. The option is documented in the clang options manual. https://clang.llvm.org/docs/ClangCommandLineReference.html#cmdoption-clang-gline-tables-only

https://github.com/llvm/llvm-project/pull/128678