[flang] [llvm] [Flang] Remove FLANG_INCLUDE_RUNTIME (PR #124126)

[Michael Kruse via llvm-commits]

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@@ -187,6 +187,19 @@ foreach(proj IN LISTS LLVM_ENABLE_RUNTIMES)
   endif()
 endforeach()
 
+option(FLANG_ENABLE_FLANG_RT "Implicitly add LLVM_ENABLE_RUNTIMES=flang-rt when compiling Flang" ON)
+if ("flang" IN_LIST LLVM_ENABLE_PROJECTS)
+  if (NOT "flang-rt" IN_LIST LLVM_ENABLE_RUNTIMES)
+    message(STATUS "Enabling Flang-RT as a dependency of Flang"
+      "Flang-RT is required for a fully working Flang toolchain."
+      "If you intend to compile Flang-RT separately following the instructions at"
+      "https://github.com/llvm/llvm-project/blob/main/flang-rt/README.md#standalone-runtimes-build"
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Meinersbur wrote:

I moved the help `message(...)` to flang/ so it is also emitted in a flang-standalone build. I also shortened it without the README link, may update it after consolidation.

https://github.com/llvm/llvm-project/pull/124126