Switch to C++17 for GUI.

Adjust compiler flags to use `-std=gnu++17` for gcc/clang instead of
`-std=gnu++11` and `/std:c++17` for msvc.

Remove Ubuntu trusty job from travis (it's too old.)

Signed-off-by: Rafael Kitover <rkitover@gmail.com>

.travis.yml

@@ -14,8 +14,6 @@ matrix:
 #          dist: bionic
 #        - env: BUILD_ENV=nostl XVFB_RUN=1
 #          dist: bionic
-        - env: BUILD_ENV=ubuntu-trusty XVFB_RUN=1
-          dist: trusty
         - env: BUILD_ENV=ubuntu-xenial XVFB_RUN=1
         - env: BUILD_ENV=ubuntu-xenial-minimal INSTALLDEPS_ARGS="--no-openal --no-ffmpeg" XVFB_RUN=1
         - env: BUILD_ENV=ubuntu-xenial XVFB_RUN=1 CC=clang CXX=clang++

CMakeLists.txt

@@ -678,7 +678,13 @@ if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID STREQUAL Clang)
 
     include(CheckCXXCompilerFlag)
 
-    set(MY_CXX_FLAGS -std=gnu++11 -fexceptions)
+    check_cxx_compiler_flag(-std=gnu++17 GNUPP17_FLAG)
+
+    if(NOT GNUPP17_FLAG)
+        message(FATAL_ERROR "Your compiler does not support -std=gnu++17.")
+    endif()
+
+    set(MY_CXX_FLAGS -std=gnu++17 -fexceptions)
 
     foreach(ARG ${MY_CXX_FLAGS})
         set(MY_CXX_FLAGS_STR "${MY_CXX_FLAGS_STR} ${ARG}")
@@ -724,6 +730,8 @@ elseif(MSVC)
     string(REGEX REPLACE "/[Ww][^ ]+" "" CMAKE_C_FLAGS   ${CMAKE_C_FLAGS})
     string(REGEX REPLACE "/[Ww][^ ]+" "" CMAKE_CXX_FLAGS ${CMAKE_CXX_FLAGS})
 
+    add_compile_options(/std:c++17)
+
     if(CMAKE_BUILD_TYPE STREQUAL Debug)
         add_compile_options(/W4)
     else()

tools/builder/core.sh

@@ -42,8 +42,8 @@ esac
 
 export CPPFLAGS="$CPPFLAGS${CPPFLAGS:+ }-I\$BUILD_ROOT/root/include -DCURL_STATICLIB -DGRAPHITE2_STATIC"
 export CFLAGS="$CFLAGS${CFLAGS:+ }-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -pthread -lm -DCURL_STATICLIB -DGRAPHITE2_STATIC"
-export CXXFLAGS="$CXXFLAGS${CXXFLAGS:+ }-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -std=gnu++11 -fpermissive -pthread -lm -DCURL_STATICLIB -DGRAPHITE2_STATIC"
-export OBJCXXFLAGS="$OBJCXXFLAGS${OBJCXXFLAGS:+ }-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -std=gnu++11 -fpermissive -pthread -lm -DCURL_STATICLIB -DGRAPHITE2_STATIC"
+export CXXFLAGS="$CXXFLAGS${CXXFLAGS:+ }-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -std=gnu++17 -fpermissive -pthread -lm -DCURL_STATICLIB -DGRAPHITE2_STATIC"
+export OBJCXXFLAGS="$OBJCXXFLAGS${OBJCXXFLAGS:+ }-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -std=gnu++17 -fpermissive -pthread -lm -DCURL_STATICLIB -DGRAPHITE2_STATIC"
 export LDFLAGS="$LDFLAGS${LDFLAGS:+ }-fPIC -L\$BUILD_ROOT/root/lib -pthread -lm"
 export STRIP="\${STRIP:-strip}"
 

tools/builder/mingw.sh

@@ -28,8 +28,8 @@ export BUILD_ENV
 : ${HOST_CXX:=ccache g++}
 : ${HOST_CPPFLAGS:="-I\$BUILD_ROOT/root/include"}
 : ${HOST_CFLAGS:="-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -pthread -lm"}
-: ${HOST_CXXFLAGS:="-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -std=gnu++11 -fpermissive -pthread -lm"}
-: ${HOST_OBJCXXFLAGS:="-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -std=gnu++11 -fpermissive -pthread -lm"}
+: ${HOST_CXXFLAGS:="-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -std=gnu++17 -fpermissive -pthread -lm"}
+: ${HOST_OBJCXXFLAGS:="-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -std=gnu++17 -fpermissive -pthread -lm"}
 : ${HOST_LDFLAGS:="-fPIC -L\$BUILD_ROOT/root/lib -pthread -lm"}
 : ${HOST_LIBS:=-lm}
 : ${HOST_UUID_LIBS:=}

tools/win/mac-cross-builder

@@ -16,8 +16,8 @@ export CC='ccache clang'
 export CXX='ccache clang++'
 export CPPFLAGS="-I\$BUILD_ROOT/root/include -DICONV_CONST="
 export CFLAGS="-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -framework Carbon -framework Foundation -framework CoreServices -Wno-unused-command-line-argument -DICONV_CONST= -Wl,-no_compact_unwind"
-export CXXFLAGS="-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -std=gnu++11 -fpermissive -stdlib=libc++ -framework Carbon -framework Foundation -framework CoreServices -Wno-unused-command-line-argument -DICONV_CONST= -Wl,-no_compact_unwind"
-export OBJCXXFLAGS="-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -std=gnu++11 -fpermissive -stdlib=libc++ -framework Carbon -framework Foundation -framework CoreServices -Wno-unused-command-line-argument -DICONV_CONST= -Wl,-no_compact_unwind"
+export CXXFLAGS="-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -std=gnu++17 -fpermissive -stdlib=libc++ -framework Carbon -framework Foundation -framework CoreServices -Wno-unused-command-line-argument -DICONV_CONST= -Wl,-no_compact_unwind"
+export OBJCXXFLAGS="-fPIC -I\$BUILD_ROOT/root/include -L\$BUILD_ROOT/root/lib -std=gnu++17 -fpermissive -stdlib=libc++ -framework Carbon -framework Foundation -framework CoreServices -Wno-unused-command-line-argument -DICONV_CONST= -Wl,-no_compact_unwind"
 export LDFLAGS="-fPIC -L\$BUILD_ROOT/root/lib -framework Carbon -framework Foundation -framework CoreServices -Wno-unused-command-line-argument -Wl,-no_compact_unwind"
 EOF
 }