Remove clang-3.5; move clang-4.0 to trusty; include <initializer_list>

.travis.yml

@@ -89,17 +89,6 @@ matrix:
           sources:
             - ubuntu-toolchain-r-test
 
-    - os: linux
-      compiler: clang++-3.5
-      env: TOOLSET=clang COMPILER=clang++-3.5 CXXSTD=c++14
-      addons:
-        apt:
-          packages:
-            - clang-3.5
-          sources:
-            - ubuntu-toolchain-r-test
-            - llvm-toolchain-precise-3.5
-
     - os: linux
       compiler: clang++-3.6
       env: TOOLSET=clang COMPILER=clang++-3.6 CXXSTD=c++14
@@ -167,6 +156,7 @@ matrix:
             - llvm-toolchain-precise-3.9
 
     - os: linux
+      dist: trusty
       compiler: clang++-4.0
       env: TOOLSET=clang COMPILER=clang++-4.0 CXXSTD=c++14
       addons:
@@ -178,6 +168,7 @@ matrix:
             - llvm-toolchain-trusty-4.0
 
     - os: linux
+      dist: trusty
       compiler: clang++-4.0
       env: TOOLSET=clang COMPILER=clang++-4.0 CXXSTD=c++1z
       addons:

include/boost/variant2/variant.hpp

@@ -15,6 +15,7 @@
 #include <type_traits>
 #include <exception>
 #include <cassert>
+#include <initializer_list>
 
 //