[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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@@ -0,0 +1,165 @@
+#===-- CMakeLists.txt ------------------------------------------------------===#
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+#===------------------------------------------------------------------------===#
+#
+# Build instructions for the flang-rt library. This is file is intended to be
+# included using the LLVM_ENABLE_RUNTIMES mechanism.
+#
+#===------------------------------------------------------------------------===#
+
+set(LLVM_SUBPROJECT_TITLE "Fortran Runtime")
+set(FLANGRT_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}")
+set(FLANGRT_BINARY_DIR "${CMAKE_CURRENT_BINARY_DIR}")
+set(FLANG_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../flang")
+
+enable_language(Fortran)
+
+list(APPEND CMAKE_MODULE_PATH
+    "${FLANGRT_SOURCE_DIR}/cmake/modules"
+    "${FLANG_SOURCE_DIR}/cmake/modules"
+  )
+include(AddFlangRT)
+include(FlangCommon)
+
+
+############################
+# Build Mode Introspection #
+############################
+
+# Setting these variables from an LLVM build is sufficient that flang-rt can
+# construct the output paths, so it can behave as if it were in-tree here.
+set(LLVM_TREE_AVAILABLE OFF)
+if (LLVM_LIBRARY_OUTPUT_INTDIR AND LLVM_RUNTIME_OUTPUT_INTDIR AND PACKAGE_VERSION)
+  # This is a bootstap build
+  set(LLVM_TREE_AVAILABLE ON)
+endif()
+
+if (LLVM_TREE_AVAILABLE)
+  # Despite Clang in the name, get_clang_resource_dir does not depend on Clang being added to the build
+  # flang-new uses the same resource dir as clang.
+  include(GetClangResourceDir)
+  get_clang_resource_dir(FLANGRT_BUILD_LIB_DIR PREFIX "${LLVM_LIBRARY_OUTPUT_INTDIR}/.." SUBDIR "lib${LLVM_LIBDIR_SUFFIX}")
+  get_clang_resource_dir(FLANGRT_INSTALL_LIB_DIR SUBDIR "lib${LLVM_LIBDIR_SUFFIX}") # No prefix, CMake's install command find the install prefix itself
+else ()
+  set(FLANGRT_BUILD_LIB_DIR "${LLVM_LIBRARY_OUTPUT_INTDIR}")
+  set(FLANGRT_INSTALL_LIB_DIR "lib${LLVM_LIBDIR_SUFFIX}")
+endif ()
+
+if (DEFINED WIN32)
+  set(FLANGRT_BUILD_LIB_DIR "${FLANGRT_BUILD_LIB_DIR}/windows")
----------------
Meinersbur wrote:

There is no `CLANG_RT`. CMake symbols of compiler-rt are prefixed with `COMPILER_RT`.

However, you are right that for cached/public CMake variables I am using `FLANG_RT` required by the LLVM_ENABLE_RUNTIMES mechanism. I just find understanding names with too many underscores more difficult: `FLANG_RT_BUILD_LIB_DIR`, `FLANG_RT_NO_GLOBAL_VAR_DEFS`, `FLANG_RT_UNITTESTS_RUNTIME_TOOLS_H_`, etc.

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