[llvm-branch-commits] [clang] [flang] [lld] [llvm] [Flang] LLVM_ENABLE_RUNTIMES=flang-rt (PR #110217)

[Michael Kruse via llvm-branch-commits]

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@@ -150,12 +150,18 @@ if ("flang" IN_LIST LLVM_ENABLE_PROJECTS)
   endif()
 endif()
 
+if ("flang-rt" IN_LIST LLVM_ENABLE_RUNTIMES)
+  if (NOT "flang" IN_LIST LLVM_ENABLE_PROJECTS)
+    message(FATAL_ERROR "Flang is not enabled, but is required for the Flang-RT runtime")
+  endif ()
+endif ()
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Meinersbur wrote:

@h-vetinari Addressed here: https://github.com/llvm/llvm-project/blob/4299d1e131df65edc4a9e8489fec8322e9f426e7/flang-rt/README.md#runtime-onlyout-of-tree-build

@jhuber6 There is one Fortran file (`flang/module/iso_fortran_env_impl.f90`, see #95388) that is compiled into an object file which is added to the runtime library. That file is actually a workaround for a symbol that depends on flang switches (`NUMERIC_STORAGE_SIZE`), but in principle there is no reason why (parts) of the runtime should not be implemented in Fortran, just like libc++ or even libc/compiler-rt is written in C++.

https://github.com/llvm/llvm-project/pull/110217