CMake: require GCC 5.0+.

.travis/install-debian.sh

@@ -1,7 +1,8 @@
 #!/bin/sh -xe
 
+sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test
 sudo apt-get update -qq
 sudo apt-get install -q -y \
   cmake cmake-data libpng12-dev zlib1g-dev libjson0-dev libfontconfig1-dev \
   libgtkmm-2.4-dev libpangomm-1.4-dev libgl1-mesa-dev libglu-dev libglew-dev \
-  libfreetype6-dev dpkg-dev
+  libfreetype6-dev dpkg-dev gcc-5 g++-5

CMakeLists.txt

@@ -53,6 +53,13 @@ if(MSVC)
     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} /Dinline=__inline")
 endif()
 
+if(CMAKE_CXX_COMPILER_ID STREQUAL GNU)
+    if(CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5.0)
+        # GCC 4.8/4.9 ship with broken but present <regex>. meh.
+        message(FATAL_ERROR "GCC 5.0+ is required")
+    endif()
+endif()
+
 if(CMAKE_CXX_COMPILER_ID STREQUAL GNU OR CMAKE_CXX_COMPILER_ID STREQUAL Clang)
     set(WARNING_FLAGS   "-Wall -Wextra -Wno-unused-parameter")
     if(CMAKE_CXX_COMPILER_ID STREQUAL Clang)

debian/rules

@@ -16,7 +16,9 @@ include /usr/share/dpkg/default.mk
 override_dh_auto_configure:
 	dh_auto_configure -- \
 	-DCMAKE_LIBRARY_PATH=$(DEB_HOST_MULTIARCH) \
-	-DCMAKE_BUILD_TYPE=$(BUILD_TYPE)
+	-DCMAKE_BUILD_TYPE=$(BUILD_TYPE) \
+  -DCMAKE_C_COMPILER=gcc-5 \
+  -DCMAKE_CXX_COMPILER=g++-5
 
 # create a -dbg package
 override_dh_strip: