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

[Joseph Huber via llvm-branch-commits]

================
@@ -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 "${FLANGRT_BUILD_LIB_DIR}/windows")
+  set(FLANGRT_INSTALL_LIB_DIR "${FLANGRT_INSTALL_LIB_DIR}/windows")
+elseif (LLVM_ENABLE_PER_TARGET_RUNTIME_DIR)
+  set(FLANGRT_BUILD_LIB_DIR "${FLANGRT_BUILD_LIB_DIR}/${LLVM_TARGET_TRIPLE}")
+  set(FLANGRT_INSTALL_LIB_DIR "${FLANGRT_INSTALL_LIB_DIR}/${LLVM_TARGET_TRIPLE}")
+endif ()
+
+
+#################
+# Build Options #
+#################
+
+# Important: flang-rt user options must be prefixed with "FLANG_RT_". Variables
+# with this prefix will be forwarded in bootstrap builds.
+
+option(FLANG_RT_INCLUDE_TESTS "Generate build targets for the flang-rt unit and regression-tests." "${LLVM_INCLUDE_TESTS}")
+
+set(FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT "" CACHE STRING "Compile flang-rt with GPU support (CUDA or OpenMP)")
+set_property(CACHE FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT PROPERTY STRINGS
+    ""
+    CUDA
+    OpenMP
+  )
+if (NOT FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT)
+elseif (FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT STREQUAL "CUDA")
+  set(FLANG_RT_LIBCUDACXX_PATH "" CACHE PATH "Path to libcu++ package installation")
+  option(FLANG_RT_CUDA_RUNTIME_PTX_WITHOUT_GLOBAL_VARS "Do not compile global variables' definitions when producing PTX library" OFF)
+elseif (FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT STREQUAL "OpenMP")
+set(FLANG_RT_DEVICE_ARCHITECTURES "all" CACHE STRING
+  "List of OpenMP device architectures to be used to compile the Fortran runtime (e.g. 'gfx1103;sm_90')")
+else ()
+  message(FATAL_ERROR "Invalid value '${FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT}' for FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT; must be empty, 'CUDA', or 'OpenMP'")
+endif ()
+
+option(FLANG_RT_ENABLE_CUF "Compile CUDA Fortran runtime sources" OFF)
+if (FLANG_RT_ENABLE_CUF)
+  find_package(CUDAToolkit REQUIRED)
+endif()
+
+
+########################
+# System Introspection #
+########################
+
+include(CheckCXXSymbolExists)
+include(CheckCXXSourceCompiles)
+check_cxx_symbol_exists(strerror_r string.h HAVE_STRERROR_R)
+# Can't use symbol exists here as the function is overloaded in C++
+check_cxx_source_compiles(
+  "#include <string.h>
+   int main() {
+     char buf[4096];
+     return strerror_s(buf, 4096, 0);
+   }
+  "
+  HAVE_DECL_STRERROR_S)
+
+
+# Search for clang_rt.builtins library.
+if (WIN32)
+  execute_process(
+      COMMAND "${CMAKE_CXX_COMPILER}" "-print-libgcc-file-name" "-rtlib=compiler-rt"
+      RESULT_VARIABLE CXX_COMPILER_PRINT_LIBGCC_PATH_FAILURE
+      OUTPUT_VARIABLE CXX_COMPILER_PRINT_LIBGCC_PATH_RESULT
+      ERROR_QUIET
+    )
+  if (NOT CXX_COMPILER_PRINT_LIBGCC_PATH_FAILURE AND CXX_COMPILER_PRINT_LIBGCC_PATH_RESULT)
+    string(STRIP "${CXX_COMPILER_PRINT_LIBGCC_PATH_RESULT}" FLANGRT_LIBCALL)
+  else ()
+    set(FLANGRT_LIBCALL "")
+  endif ()
+endif ()
+
+
+#####################
+# Build Preparation #
+#####################
+
+if (FLANG_RT_EXPERIMENTAL_OFFLOAD_SUPPORT AND FLANG_RT_INCLUDE_TESTS)
+  # If Fortran runtime is built as CUDA library, the linking
+  # of targets that link flang-rt must be done
+  # with CUDA_RESOLVE_DEVICE_SYMBOLS.
+  # CUDA language must be enabled for CUDA_RESOLVE_DEVICE_SYMBOLS
+  # to take effect.
+  enable_language(CUDA)
+endif()
+
+
+# C++17 is required for flang-rt; user or other runtimes may override this.
+# GTest included later also requires C++17.
+set(CMAKE_CXX_STANDARD 17 CACHE STRING "C++ standard to conform to")
+set(CMAKE_CXX_STANDARD_REQUIRED YES)
+
+# Disable libstdc++/libc++ assertions, even in an LLVM_ENABLE_ASSERTIONS build,
+# to avoid an unwanted dependency on libstdc++/libc++.so.
+add_definitions(-U_GLIBCXX_ASSERTIONS)
+add_definitions(-U_LIBCPP_ENABLE_ASSERTIONS)
----------------
jhuber6 wrote:

I'm guessing this comes from the headers? This seems really questionable so it would be nice if there were another way, or just remove whatever dependency pulls it in.

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