From 1f0ba0ea084c575d5e8c261b3928f7beb08d6f0d Mon Sep 17 00:00:00 2001
From: Fabio Bas <ctrlaltca@gmail.com>
Date: Fri, 25 Jul 2014 17:32:12 +0200
Subject: [PATCH] Debug compilation: check flags actually supported by the
 compiler

---
 CMakeLists.txt | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 825ed5cb..d0d40591 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -76,8 +76,19 @@ IF(MSVC)
     #set(CMAKE_CXX_FLAGS_DEBUG "/Zi")
 ELSEIF (CMAKE_COMPILER_IS_GNUCXX)
     # linux/gcc, bsd/gcc, windows/mingw
+    include(CheckCXXCompilerFlag)
+
     set(CMAKE_CXX_FLAGS_RELEASE "-s -O2")
-    set(CMAKE_CXX_FLAGS_DEBUG "-ggdb -O0 -Wall -Wextra -pedantic -Werror -Wcast-align -Wmissing-declarations -Winline -Wno-long-long -Wno-error=extra -Wno-error=unused-parameter -Wno-inline -Wno-error=delete-non-virtual-dtor -Wno-error=sign-compare -Wno-error=reorder -Wno-error=missing-declarations")
+    set(CMAKE_CXX_FLAGS_DEBUG "-ggdb -O0 -Wall -Wextra -pedantic -Werror")
+
+    set(ADDITIONAL_DEBUG_FLAGS -Wcast-align -Wmissing-declarations -Winline -Wno-long-long -Wno-error=extra -Wno-error=unused-parameter -Wno-inline -Wno-error=delete-non-virtual-dtor -Wno-error=sign-compare -Wno-error=reorder -Wno-error=missing-declarations)
+
+    FOREACH(FLAG ${ADDITIONAL_DEBUG_FLAGS})
+        CHECK_CXX_COMPILER_FLAG("${FLAG}" CXX_HAS_WARNING_${FLAG})
+        IF(CXX_HAS_WARNING_${FLAG})
+            SET(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} ${FLAG}")
+        ENDIF()
+    ENDFOREACH()
 ELSE()
     # other: osx/llvm, bsd/llvm
     set(CMAKE_CXX_FLAGS_RELEASE "-O2")