1 files changed, 97 insertions, 0 deletions
diff --git a/cmake/Compiler.cmake b/cmake/Compiler.cmake
new file mode 100644
index 0000000..bd0b352
--- /dev/null
+++ b/cmake/Compiler.cmake
@@ -0,0 +1,97 @@
+# HyBBX toolchain detection and portable warning flags.
+#
+# Supported compilers: GCC (primary), LLVM Clang.
+# Supported OS families: Linux, *BSD (FreeBSD, NetBSD, OpenBSD, …), MacOS X+,
+#   Windows 10+ (MinGW/Clang), AmigaOS 3.9+ (cross-GCC). POSIX+ friendly.
+
+include(CheckCCompilerFlag)
+
+set(HYBBX_COMPILER_GCC FALSE)
+set(HYBBX_COMPILER_CLANG FALSE)
+set(HYBBX_COMPILER_APPLECLANG FALSE)
+
+if(CMAKE_C_COMPILER_ID STREQUAL "GNU")
+    set(HYBBX_COMPILER_GCC TRUE)
+elseif(CMAKE_C_COMPILER_ID STREQUAL "Clang")
+    if(CMAKE_C_COMPILER_FRONTEND_VARIANT STREQUAL "MSVC")
+        message(FATAL_ERROR "HyBBX requires GCC or Clang.")
+    endif()
+    set(HYBBX_COMPILER_CLANG TRUE)
+elseif(CMAKE_C_COMPILER_ID STREQUAL "AppleClang")
+    set(HYBBX_COMPILER_CLANG TRUE)
+    set(HYBBX_COMPILER_APPLECLANG TRUE)
+elseif(CMAKE_C_COMPILER_ID STREQUAL "MSVC")
+    message(FATAL_ERROR "HyBBX requires GCC or Clang.")
+else()
+    message(WARNING
+        "HyBBX is developed with GCC (primary) and Clang. "
+        "Compiler '${CMAKE_C_COMPILER_ID}' is untested.")
+endif()
+
+function(hybbx_probe_c_flag flag out_var)
+    string(REGEX REPLACE "[^a-zA-Z0-9]+" "_" flag_id "${flag}")
+    set(cache_var "HYBBX_C_FLAG_${flag_id}")
+    if(NOT DEFINED ${cache_var})
+        check_c_compiler_flag("${flag}" ${cache_var})
+    endif()
+    if(${cache_var})
+        set(${out_var} TRUE PARENT_SCOPE)
+    else()
+        set(${out_var} FALSE PARENT_SCOPE)
+    endif()
+endfunction()
+
+function(hybbx_collect_supported_c_flags)
+    set(_candidates
+        -Wall
+        -Wextra
+        -Wpedantic
+        -Wformat=2
+        -Wstrict-prototypes
+        -Wmissing-prototypes
+        -Wwrite-strings
+        -Wshadow
+        -fno-strict-aliasing
+    )
+
+    if(NOT HYBBX_PLATFORM_AMIGAOS)
+        list(APPEND _candidates -fstack-protector-strong)
+    endif()
+
+    if(HYBBX_COMPILER_GCC)
+        list(APPEND _candidates
+            -Wduplicated-cond
+            -Wnull-dereference
+            -Wlogical-op
+            -Wformat-signedness
+        )
+        if(NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 8.0 AND NOT HYBBX_PLATFORM_AMIGAOS)
+            list(APPEND _candidates -fstack-clash-protection)
+        endif()
+    endif()
+
+    if(HYBBX_COMPILER_CLANG AND NOT HYBBX_COMPILER_APPLECLANG)
+        list(APPEND _candidates -Wno-gnu-zero-variadic-macro-arguments)
+    endif()
+
+    set(_supported "")
+    foreach(flag IN LISTS _candidates)
+        hybbx_probe_c_flag("${flag}" _ok)
+        if(_ok)
+            list(APPEND _supported "${flag}")
+        endif()
+    endforeach()
+
+    set(HYBBX_SUPPORTED_C_FLAGS "${_supported}" CACHE INTERNAL
+        "C warning/security flags supported by ${CMAKE_C_COMPILER_ID}")
+endfunction()
+
+hybbx_collect_supported_c_flags()
+
+if(HYBBX_COMPILER_GCC)
+    message(STATUS "HyBBX compiler: GCC ${CMAKE_C_COMPILER_VERSION} (primary)")
+elseif(HYBBX_COMPILER_CLANG)
+    message(STATUS "HyBBX compiler: Clang ${CMAKE_C_COMPILER_VERSION}")
+else()
+    message(STATUS "HyBBX compiler: ${CMAKE_C_COMPILER_ID} ${CMAKE_C_COMPILER_VERSION}")
+endif()