From: Alexander Lanin <alex@lanin.de>
Date: Fri, 23 Oct 2020 13:30:54 +0000 (+0200)
Subject: Fail gracefully on ancient compilers (#702)
X-Git-Tag: v4.1~47
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=08b3c4765a7ccdb8f3f2d260e44e08d6189b7508;p=thirdparty%2Fccache.git

Fail gracefully on ancient compilers (#702)
---

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 77fbd2ccc..ebecf441a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -16,6 +16,29 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS TRUE)
 
 list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 
+#
+#
+# Minimum compiler requirements
+# (Fail gracefully instead of cryptic C++ error messages)
+#
+#
+
+# Clang 3.4 and AppleClang 6.0 do not compile doctest.
+# Gcc 4.8.5 has been the minimum version for quite a while.
+if((CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.5)
+OR (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.8.5)
+OR (CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 7.0))
+  message(FATAL_ERROR "The compiler you are using is too old, sorry.\nYou need one listed here: https://ccache.dev/platform-compiler-language-support.html")
+endif()
+
+# All Clang problems / special handling ccache has is because of 3.5.
+# All gcc problems / special handling ccache has is because of 4.8.5.
+if((CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.6)
+OR (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5.0))
+  message(WARNING "The compiler you are using is rather old.\nIf anything goes wrong you might be better of with one listed here: https://ccache.dev/platform-compiler-language-support.html")
+endif()
+
+
 #
 # Settings
 #