1 files changed, 110 insertions, 0 deletions
diff --git a/rcc/cmake/modules/CheckCompilerVersion.cmake b/rcc/cmake/modules/CheckCompilerVersion.cmake
new file mode 100644
index 0000000..7a9f964
--- /dev/null
+++ b/rcc/cmake/modules/CheckCompilerVersion.cmake
@@ -0,0 +1,110 @@
+# Check if the host compiler is new enough.
+# These versions are updated based on the following policy:
+#   rcc.org/docs/DeveloperPolicy.html#toolchain
+
+include(CheckCXXSourceCompiles)
+
+set(GCC_MIN 7.4)
+set(GCC_SOFT_ERROR 7.4)
+set(CLANG_MIN 5.0)
+set(CLANG_SOFT_ERROR 5.0)
+set(APPLECLANG_MIN 10.0)
+set(APPLECLANG_SOFT_ERROR 10.0)
+
+# https://en.wikipedia.org/wiki/Microsoft_Visual_C#Internal_version_numbering
+# _MSC_VER == 1928 MSVC++ 19.27 Visual Studio 2019 Version 16.8 + 16.9
+set(MSVC_MIN 19.28)
+set(MSVC_SOFT_ERROR 19.28)
+
+set(LIBSTDCXX_MIN 7)
+set(LIBSTDCXX_SOFT_ERROR 7)
+
+
+if(DEFINED RCC_COMPILER_CHECKED)
+  return()
+endif()
+set(RCC_COMPILER_CHECKED ON)
+
+if(RCC_FORCE_USE_OLD_TOOLCHAIN)
+  return()
+endif()
+
+function(check_compiler_version NAME NICE_NAME MINIMUM_VERSION SOFT_ERROR_VERSION)
+  if(NOT CMAKE_CXX_COMPILER_ID STREQUAL NAME)
+    return()
+  endif()
+  if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS MINIMUM_VERSION)
+    message(FATAL_ERROR "Host ${NICE_NAME} version must be at least ${MINIMUM_VERSION}, your version is ${CMAKE_CXX_COMPILER_VERSION}.")
+  elseif(CMAKE_CXX_COMPILER_VERSION VERSION_LESS SOFT_ERROR_VERSION)
+    if(RCC_TEMPORARILY_ALLOW_OLD_TOOLCHAIN)
+      message(WARNING "Host ${NICE_NAME} version should be at least ${SOFT_ERROR_VERSION} because RCC will soon use new C++ features which your toolchain version doesn't support. Your version is ${CMAKE_CXX_COMPILER_VERSION}. Ignoring because you've set RCC_TEMPORARILY_ALLOW_OLD_TOOLCHAIN, but very soon your toolchain won't be supported.")
+    else()
+      message(FATAL_ERROR "Host ${NICE_NAME} version should be at least ${SOFT_ERROR_VERSION} because RCC will soon use new C++ features which your toolchain version doesn't support. Your version is ${CMAKE_CXX_COMPILER_VERSION}. You can temporarily opt out using RCC_TEMPORARILY_ALLOW_OLD_TOOLCHAIN, but very soon your toolchain won't be supported.")
+    endif()
+  endif()
+endfunction(check_compiler_version)
+
+check_compiler_version("GNU" "GCC" ${GCC_MIN} ${GCC_SOFT_ERROR})
+check_compiler_version("Clang" "Clang" ${CLANG_MIN} ${CLANG_SOFT_ERROR})
+check_compiler_version("AppleClang" "Apple Clang" ${APPLECLANG_MIN} ${APPLECLANG_SOFT_ERROR})
+check_compiler_version("MSVC" "Visual Studio" ${MSVC_MIN} ${MSVC_SOFT_ERROR})
+
+# See https://developercommunity.visualstudio.com/content/problem/845933/miscompile-boolean-condition-deduced-to-be-always.html
+# and thread "[rcc-dev] Longstanding failing tests - clang-tidy, MachO, Polly"
+# on rcc-dev Jan 21-23 2020.
+if ((${CMAKE_CXX_COMPILER_ID} STREQUAL MSVC) AND
+    (19.24 VERSION_LESS_EQUAL ${CMAKE_CXX_COMPILER_VERSION}) AND
+    (${CMAKE_CXX_COMPILER_VERSION} VERSION_LESS 19.25))
+  if(RCC_TEMPORARILY_ALLOW_OLD_TOOLCHAIN)
+    message(WARNING "Host Visual Studio version 16.4 is known to miscompile part of RCC")
+  else()
+    message(FATAL_ERROR "Host Visual Studio version 16.4 is known to miscompile part of RCC, please use clang-cl or upgrade to 16.5 or above (use -DRCC_TEMPORARILY_ALLOW_OLD_TOOLCHAIN=ON to ignore)")
+  endif()
+endif()
+
+
+if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+  if (CMAKE_CXX_SIMULATE_ID MATCHES "MSVC")
+    if (CMAKE_CXX_SIMULATE_VERSION VERSION_LESS MSVC_MIN)
+      message(FATAL_ERROR "Host Clang must have at least -fms-compatibility-version=${MSVC_MIN}, your version is ${CMAKE_CXX_SIMULATE_VERSION}.")
+    endif()
+    set(CLANG_CL 1)
+  elseif(NOT RCC_ENABLE_LIBCXX)
+    # Test that we aren't using too old of a version of libstdc++.
+    set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
+    set(OLD_CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
+    set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -std=c++0x")
+    check_cxx_source_compiles("
+#include <iosfwd>
+#if defined(__GLIBCXX__)
+#if !defined(_GLIBCXX_RELEASE) || _GLIBCXX_RELEASE < ${LIBSTDCXX_MIN}
+#error Unsupported libstdc++ version
+#endif
+#endif
+int main() { return 0; }
+"
+      RCC_LIBSTDCXX_MIN)
+    if(NOT RCC_LIBSTDCXX_MIN)
+      message(FATAL_ERROR "libstdc++ version must be at least ${GCC_MIN}.")
+    endif()
+    check_cxx_source_compiles("
+#include <iosfwd>
+#if defined(__GLIBCXX__)
+#if !defined(_GLIBCXX_RELEASE) || _GLIBCXX_RELEASE < ${LIBSTDCXX_SOFT_ERROR}
+#error Unsupported libstdc++ version
+#endif
+#endif
+int main() { return 0; }
+"
+      RCC_LIBSTDCXX_SOFT_ERROR)
+    if(NOT RCC_LIBSTDCXX_SOFT_ERROR)
+      if(RCC_TEMPORARILY_ALLOW_OLD_TOOLCHAIN)
+        message(WARNING "libstdc++ version should be at least ${LIBSTDCXX_SOFT_ERROR} because RCC will soon use new C++ features which your toolchain version doesn't support. Ignoring because you've set RCC_TEMPORARILY_ALLOW_OLD_TOOLCHAIN, but very soon your toolchain won't be supported.")
+      else()
+        message(FATAL_ERROR "libstdc++ version should be at least ${LIBSTDCXX_SOFT_ERROR} because RCC will soon use new C++ features which your toolchain version doesn't support. You can temporarily opt out using RCC_TEMPORARILY_ALLOW_OLD_TOOLCHAIN, but very soon your toolchain won't be supported.")
+      endif()
+    endif()
+    set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
+    set(CMAKE_REQUIRED_LIBRARIES ${OLD_CMAKE_REQUIRED_LIBRARIES})
+  endif()
+endif()