diff --git a/.travis.yml b/.travis.yml
index fc68de4..13bd0d2 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,4 +1,5 @@
 # Copyright 2016, 2017, 2018 Peter Dimov
+# Copyright 2019 Andrey Semashev
 # Distributed under the Boost Software License, Version 1.0.
 # (See accompanying file LICENSE_1_0.txt or copy at http://boost.org/LICENSE_1_0.txt)
 
@@ -22,12 +23,10 @@ matrix:
     - env: BOGUS_JOB=true
 
   include:
+# gcc, Linux
     - os: linux
-      compiler: g++
-      env: TOOLSET=gcc COMPILER=g++ CXXSTD=03,11
-
-    - os: linux
-      compiler: g++-4.4
+      dist: trusty
+      compiler: gcc-4.4
       env: TOOLSET=gcc COMPILER=g++-4.4 CXXSTD=98,0x
       addons:
         apt:
@@ -37,7 +36,8 @@ matrix:
             - ubuntu-toolchain-r-test
 
     - os: linux
-      compiler: g++-4.6
+      dist: trusty
+      compiler: gcc-4.6
       env: TOOLSET=gcc COMPILER=g++-4.6 CXXSTD=03,0x
       addons:
         apt:
@@ -47,7 +47,8 @@ matrix:
             - ubuntu-toolchain-r-test
 
     - os: linux
-      compiler: g++-4.7
+      dist: trusty
+      compiler: gcc-4.7
       env: TOOLSET=gcc COMPILER=g++-4.7 CXXSTD=03,11
       addons:
         apt:
@@ -57,7 +58,8 @@ matrix:
             - ubuntu-toolchain-r-test
 
     - os: linux
-      compiler: g++-4.8
+      dist: xenial
+      compiler: gcc-4.8
       env: TOOLSET=gcc COMPILER=g++-4.8 CXXSTD=03,11
       addons:
         apt:
@@ -65,8 +67,10 @@ matrix:
             - g++-4.8
           sources:
             - ubuntu-toolchain-r-test
+
     - os: linux
-      compiler: g++-4.9
+      dist: xenial
+      compiler: gcc-4.9
       env: TOOLSET=gcc COMPILER=g++-4.9 CXXSTD=03,11
       addons:
         apt:
@@ -76,7 +80,8 @@ matrix:
             - ubuntu-toolchain-r-test
 
     - os: linux
-      compiler: g++-5
+      dist: xenial
+      compiler: gcc-5
       env: TOOLSET=gcc COMPILER=g++-5 CXXSTD=03,11,14,1z
       addons:
         apt:
@@ -86,7 +91,8 @@ matrix:
             - ubuntu-toolchain-r-test
 
     - os: linux
-      compiler: g++-6
+      dist: xenial
+      compiler: gcc-6
       env: TOOLSET=gcc COMPILER=g++-6 CXXSTD=03,11,14,1z
       addons:
         apt:
@@ -96,7 +102,8 @@ matrix:
             - ubuntu-toolchain-r-test
 
     - os: linux
-      compiler: g++-7
+      dist: xenial
+      compiler: gcc-7
       env: TOOLSET=gcc COMPILER=g++-7 CXXSTD=03,11,14,17
       addons:
         apt:
@@ -106,7 +113,8 @@ matrix:
             - ubuntu-toolchain-r-test
 
     - os: linux
-      compiler: g++-8
+      dist: xenial
+      compiler: gcc-8
       env: TOOLSET=gcc COMPILER=g++-8 CXXSTD=03,11,14,17
       addons:
         apt:
@@ -116,27 +124,34 @@ matrix:
             - ubuntu-toolchain-r-test
 
     - os: linux
-      compiler: clang++
-      env: TOOLSET=clang COMPILER=clang++ CXXSTD=03,11
-
-    - os: linux
-      compiler: /usr/bin/clang++
-      env: TOOLSET=clang COMPILER=/usr/bin/clang++ CXXSTD=03,11
+      dist: bionic
+      compiler: gcc-9
+      env: TOOLSET=gcc COMPILER=g++-9 CXXSTD=03,11,14,17
       addons:
         apt:
           packages:
-            - clang-3.3
+            - g++-9
+          sources:
+            - sourceline: "ppa:ubuntu-toolchain-r/test"
 
+# clang, Linux
     - os: linux
-      compiler: /usr/bin/clang++
-      env: TOOLSET=clang COMPILER=/usr/bin/clang++ CXXSTD=03,11
+      dist: trusty
+      compiler: clang-3.4
+      env: TOOLSET=clang COMPILER=clang++-3.4 CXXSTD=03,11
       addons:
         apt:
           packages:
             - clang-3.4
+            - libstdc++-4.9-dev
+          sources:
+            - ubuntu-toolchain-r-test
+            - sourceline: "deb http://apt.llvm.org/trusty/ llvm-toolchain-trusty-3.4 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
 
     - os: linux
-      compiler: clang++-3.5
+      dist: trusty
+      compiler: clang-3.5
       env: TOOLSET=clang COMPILER=clang++-3.5 CXXSTD=03,11,14,1z
       addons:
         apt:
@@ -145,109 +160,176 @@ matrix:
             - libstdc++-4.9-dev
           sources:
             - ubuntu-toolchain-r-test
-            - llvm-toolchain-precise-3.5
+            - sourceline: "deb http://apt.llvm.org/trusty/ llvm-toolchain-trusty-3.5 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
 
     - os: linux
-      compiler: clang++-3.6
+      dist: trusty
+      compiler: clang-3.6
       env: TOOLSET=clang COMPILER=clang++-3.6 CXXSTD=03,11,14,1z
       addons:
         apt:
           packages:
             - clang-3.6
+            - libstdc++-5-dev
           sources:
             - ubuntu-toolchain-r-test
-            - llvm-toolchain-precise-3.6
+            - sourceline: "deb http://apt.llvm.org/trusty/ llvm-toolchain-trusty-3.6 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
 
     - os: linux
-      compiler: clang++-3.7
+      dist: trusty
+      compiler: clang-3.7
       env: TOOLSET=clang COMPILER=clang++-3.7 CXXSTD=03,11,14,1z
       addons:
         apt:
           packages:
             - clang-3.7
+            - libstdc++-5-dev
           sources:
             - ubuntu-toolchain-r-test
-            - llvm-toolchain-precise-3.7
+            - sourceline: "deb http://apt.llvm.org/trusty/ llvm-toolchain-trusty-3.7 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
 
     - os: linux
-      compiler: clang++-3.8
+      dist: xenial
+      compiler: clang-3.8
       env: TOOLSET=clang COMPILER=clang++-3.8 CXXSTD=03,11,14,1z
       addons:
         apt:
           packages:
             - clang-3.8
-            - libstdc++-4.9-dev
+            - libstdc++-6-dev
           sources:
             - ubuntu-toolchain-r-test
-            - llvm-toolchain-precise-3.8
+            - sourceline: "deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-3.8 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
 
     - os: linux
-      compiler: clang++-3.9
+      dist: xenial
+      compiler: clang-3.9
       env: TOOLSET=clang COMPILER=clang++-3.9 CXXSTD=03,11,14,1z
       addons:
         apt:
           packages:
             - clang-3.9
-            - libstdc++-4.9-dev
+            - libstdc++-6-dev
           sources:
             - ubuntu-toolchain-r-test
-            - llvm-toolchain-precise-3.9
+            - sourceline: "deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-3.9 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
 
     - os: linux
-      compiler: clang++-4.0
+      dist: xenial
+      compiler: clang-4
       env: TOOLSET=clang COMPILER=clang++-4.0 CXXSTD=03,11,14,1z
       addons:
         apt:
           packages:
             - clang-4.0
+            - libstdc++-6-dev
           sources:
             - ubuntu-toolchain-r-test
-            - llvm-toolchain-trusty-4.0
+            - sourceline: "deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-4.0 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
 
     - os: linux
-      compiler: clang++-5.0
+      dist: xenial
+      compiler: clang-5
       env: TOOLSET=clang COMPILER=clang++-5.0 CXXSTD=03,11,14,1z
       addons:
         apt:
           packages:
             - clang-5.0
+            - libstdc++-7-dev
           sources:
             - ubuntu-toolchain-r-test
-            - llvm-toolchain-trusty-5.0
+            - sourceline: "deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-5.0 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
 
     - os: linux
-      compiler: clang++-6.0
-      env: TOOLSET=clang COMPILER=clang++-6.0 CXXSTD=03,11,14,1z
+      dist: xenial
+      compiler: clang-6
+      env: TOOLSET=clang COMPILER=clang++-6.0 CXXSTD=03,11,14,17
       addons:
         apt:
           packages:
             - clang-6.0
+            - libstdc++-8-dev
           sources:
             - ubuntu-toolchain-r-test
-            - llvm-toolchain-trusty-6.0
+            - sourceline: "deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-6.0 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
 
     - os: linux
-      compiler: clang++-7
+      dist: xenial
+      compiler: clang-7
       env: TOOLSET=clang COMPILER=clang++-7 CXXSTD=03,11,14,17
       addons:
         apt:
           packages:
             - clang-7
+            - libstdc++-8-dev
           sources:
             - ubuntu-toolchain-r-test
-            - llvm-toolchain-trusty-7
+            - sourceline: "deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-7 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
 
     - os: linux
-      compiler: clang++-libc++
-      env: TOOLSET=clang COMPILER=clang++-libc++ CXXSTD=03,11,14,1z
+      dist: xenial
+      compiler: clang-8
+      env: TOOLSET=clang COMPILER=clang++-8 CXXSTD=03,11,14,17
       addons:
         apt:
           packages:
-            - libc++-dev
+            - clang-8
+            - libstdc++-8-dev
+          sources:
+            - ubuntu-toolchain-r-test
+            - sourceline: "deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-8 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
+
+    - os: linux
+      dist: xenial
+      compiler: clang-9
+      env: TOOLSET=clang COMPILER=clang++-9 CXXSTD=03,11,14,17
+      addons:
+        apt:
+          packages:
+            - clang-9
+            - libstdc++-9-dev
+          sources:
+            - sourceline: "ppa:ubuntu-toolchain-r/test"
+            - sourceline: "deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-9 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
+
+    - os: linux
+      dist: xenial
+      compiler: clang-libc++
+      env: TOOLSET=clang COMPILER=clang++-9 CXXSTD=03,11,14,17 CXXFLAGS="-stdlib=libc++" LINKFLAGS="-stdlib=libc++"
+      addons:
+        apt:
+          packages:
+            - clang-9
+            - libc++-9-dev
+            - libc++abi-9-dev
+          sources:
+            - sourceline: "ppa:ubuntu-toolchain-r/test"
+            - sourceline: "deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-9 main"
+              key_url: "https://apt.llvm.org/llvm-snapshot.gpg.key"
+
+# clang, OS X
+    - os: osx
+      env: TOOLSET=clang COMPILER=clang++ CXXSTD=03,11,14,1z
+      osx_image: xcode9.4
 
     - os: osx
-      compiler: clang++
       env: TOOLSET=clang COMPILER=clang++ CXXSTD=03,11,14,1z
+      osx_image: xcode10.3
+
+    - os: osx
+      env: TOOLSET=clang COMPILER=clang++ CXXSTD=03,11,14,17
+      osx_image: xcode11.2
 
 install:
   - GIT_FETCH_JOBS=8
@@ -271,7 +353,7 @@ script:
   - |-
     echo "using $TOOLSET : : $COMPILER ;" > ~/user-config.jam
   - BUILD_JOBS=`(nproc || sysctl -n hw.ncpu) 2> /dev/null`
-  - ./b2 -j $BUILD_JOBS libs/detail/test toolset=$TOOLSET cxxstd=$CXXSTD
+  - ./b2 -j $BUILD_JOBS libs/detail/test toolset=$TOOLSET cxxstd=$CXXSTD ${CXXFLAGS:+cxxflags="$CXXFLAGS"} ${LINKFLAGS:+linkflags="$LINKFLAGS"}
 
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