diff --git a/.travis.yml b/.travis.yml
index afdd6690..02cc2af7 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,21 +1,38 @@
 sudo: false
 language: cpp
 
+notifications:
+  email: false
+
 branches:
   only:
     - devel
     - travis
 
+addons:
+  sources: &apt_sources
+    - ubuntu-toolchain-r-test
+    - llvm-toolchain-precise-3.5
+    - llvm-toolchain-precise-3.6
+    - llvm-toolchain-precise-3.7
+    - llvm-toolchain-precise-3.8
+
+env:
+  global:
+    - C= B=
+  matrix:
+    - TRAVIS_EMPTY_JOB_WORKAROUND=true
+
 matrix:
+  exclude:
+    - env: TRAVIS_EMPTY_JOB_WORKAROUND=true
   include:
     - os: linux
       compiler: clang
       env: C=clang-m32 B=debug
       addons:
         apt:
-          packages:
-            - g++-multilib
-            - zlib1g-dev:i386
+          packages: [ "g++-multilib", "zlib1g-dev:i386" ]
     - os: linux
       compiler: clang
       env: C=clang-m64 B=debug
@@ -24,20 +41,72 @@ matrix:
       env: C=clang-m32
       addons:
         apt:
-          packages:
-            - g++-multilib
-            - zlib1g-dev:i386
+          packages: [ "g++-multilib", "zlib1g-dev:i386" ]
     - os: linux
       compiler: clang
       env: C=clang-m64
+    - os: linux
+      compiler: clang
+      env: C=clang-3.5-m32
+      addons:
+        apt:
+          sources: *apt_sources
+          packages: [ "clang-3.5", "g++-6-multilib", "zlib1g-dev:i386" ]
+    - os: linux
+      compiler: clang
+      env: C=clang-3.5-m64
+      addons:
+        apt:
+          sources: *apt_sources
+          packages: [ "clang-3.5" ]
+    - os: linux
+      compiler: clang
+      env: C=clang-3.6-m32
+      addons:
+        apt:
+          sources: *apt_sources
+          packages: [ "clang-3.6", "g++-6-multilib", "zlib1g-dev:i386" ]
+    - os: linux
+      compiler: clang
+      env: C=clang-3.6-m64
+      addons:
+        apt:
+          sources: *apt_sources
+          packages: [ "clang-3.6" ]
+    - os: linux
+      compiler: clang
+      env: C=clang-3.7-m32
+      addons:
+        apt:
+          sources: *apt_sources
+          packages: [ "clang-3.7", "g++-6-multilib", "zlib1g-dev:i386" ]
+    - os: linux
+      compiler: clang
+      env: C=clang-3.7-m64
+      addons:
+        apt:
+          sources: *apt_sources
+          packages: [ "clang-3.7" ]
+    - os: linux
+      compiler: clang
+      env: C=clang-3.8-m32
+      addons:
+        apt:
+          sources: *apt_sources
+          packages: [ "clang-3.8", "g++-6-multilib", "zlib1g-dev:i386" ]
+    - os: linux
+      compiler: clang
+      env: C=clang-3.8-m64
+      addons:
+        apt:
+          sources: *apt_sources
+          packages: [ "clang-3.8" ]
     - os: linux
       compiler: gcc
       env: C=gcc-m32
       addons:
         apt:
-          packages:
-            - g++-multilib
-            - zlib1g-dev:i386
+          packages: [ "g++-multilib", "zlib1g-dev:i386" ]
     - os: linux
       compiler: gcc
       env: C=gcc-m64
@@ -46,62 +115,62 @@ matrix:
       env: C=gcc-5-m32
       addons:
         apt:
-          sources:
-            - ubuntu-toolchain-r-test
-          packages:
-            - g++-5-multilib
-            - zlib1g-dev:i386
+          sources: *apt_sources
+          packages: [ "g++-5-multilib", "zlib1g-dev:i386" ]
     - os: linux
       compiler: gcc-5
       env: C=gcc-5-m64
       addons:
         apt:
-          sources:
-            - ubuntu-toolchain-r-test
-          packages:
-            - g++-5
+          sources: *apt_sources
+          packages: [ "g++-5" ]
     - os: linux
       compiler: gcc-6
       env: C=gcc-6-m32
       addons:
         apt:
-          sources:
-            - ubuntu-toolchain-r-test
-          packages:
-            - g++-6-multilib
-            - zlib1g-dev:i386
+          sources: *apt_sources
+          packages: [ "g++-6-multilib", "zlib1g-dev:i386" ]
     - os: linux
       compiler: gcc-6
       env: C=gcc-6-m64
       addons:
         apt:
-          sources:
-            - ubuntu-toolchain-r-test
-          packages:
-            - g++-6
+          sources: *apt_sources
+          packages: [ "g++-6" ]
     - os: linux
       compiler: gcc-6
-      # FIXME: linking fails - need updated binutils?
-      env: C=gcc-6-m64 B=sanitize ALLOW_FAIL=1
+      env: C=gcc-6-m64 B=debug+sanitize
       addons:
         apt:
-          sources:
-            - ubuntu-toolchain-r-test
-          packages:
-            - g++-6
+          sources: *apt_sources
+          packages: [ "g++-6" ]
+    - os: linux
+      compiler: gcc-6
+      env: C=gcc-6-m64 B=debug+valgrind
+      addons:
+        apt:
+          sources: *apt_sources
+          packages: [ "g++-6", "valgrind" ]
     - os: osx
       compiler: clang
-      env: C=clang-m64 B=debug
-      #osx_image: xcode7
+      env: C=clang-m32
+      osx_image: xcode7.3
     - os: osx
       compiler: clang
-      # FIXME: linking fails with "ld: internal error: atom not found"
-      env: C=clang-m64 B=release ALLOW_FAIL=1
-      #osx_image: xcode7
+      env: C=clang-m64
+      osx_image: xcode7.3
+    - os: osx
+      compiler: clang
+      env: C=clang-m32
+      osx_image: xcode8
+    - os: osx
+      compiler: clang
+      env: C=clang-m64
+      osx_image: xcode8
 
 install:
-  - DEPS_DIR="$TRAVIS_BUILD_DIR/deps"
-  - mkdir -p "$DEPS_DIR" && cd "$DEPS_DIR"
+  - DEPS_DIR="$TRAVIS_BUILD_DIR/deps"; mkdir -p "$DEPS_DIR" && cd "$DEPS_DIR"
   - wget --no-check-certificate -q -O - https://download.freenas.org/distfiles/ucl-1.03.tar.gz | tar -xz
   - git clone https://github.com/upx/upx-testsuite
 
diff --git a/.travis_build.sh b/.travis_build.sh
index cce03256..8e51cac4 100644
--- a/.travis_build.sh
+++ b/.travis_build.sh
@@ -10,6 +10,18 @@ BUILD_METHOD="$B"
 case $C in
     clang-m32) CC="clang -m32"; CXX="clang++ -m32" ;;
     clang-m64) CC="clang -m64"; CXX="clang++ -m64" ;;
+    clang-3.4-m32) CC="clang-3.4 -m32"; CXX="clang++-3.4 -m32" ;;
+    clang-3.4-m64) CC="clang-3.4 -m64"; CXX="clang++-3.4 -m64" ;;
+    clang-3.5-m32) CC="clang-3.5 -m32"; CXX="clang++-3.5 -m32" ;;
+    clang-3.5-m64) CC="clang-3.5 -m64"; CXX="clang++-3.5 -m64" ;;
+    clang-3.6-m32) CC="clang-3.6 -m32"; CXX="clang++-3.6 -m32" ;;
+    clang-3.6-m64) CC="clang-3.6 -m64"; CXX="clang++-3.6 -m64" ;;
+    clang-3.7-m32) CC="clang-3.7 -m32"; CXX="clang++-3.7 -m32" ;;
+    clang-3.7-m64) CC="clang-3.7 -m64"; CXX="clang++-3.7 -m64" ;;
+    clang-3.8-m32) CC="clang-3.8 -m32"; CXX="clang++-3.8 -m32" ;;
+    clang-3.8-m64) CC="clang-3.8 -m64"; CXX="clang++-3.8 -m64" ;;
+    clang-3.9-m32) CC="clang-3.9 -m32"; CXX="clang++-3.9 -m32" ;;
+    clang-3.9-m64) CC="clang-3.9 -m64"; CXX="clang++-3.9 -m64" ;;
     gcc-m32) CC="gcc -m32"; CXX="g++ -m32" ;;
     gcc-m64) CC="gcc -m64"; CXX="g++ -m64" ;;
     gcc-5-m32) CC="gcc-5 -m32"; CXX="g++-5 -m32" ;;
@@ -71,23 +83,27 @@ mkdir -p "$BUILD_DIR"
 
 # build UCL
 cd /; cd "$UPX_UCLDIR" || exit 1
-./configure --enable-static --disable-shared
+./configure --enable-static --disable-shared --disable-asm
 make
 
 # build UPX
 cd /; cd "$BUILD_DIR" || exit 1
-f="EXTRA_CPPFLAGS=-DUCL_NO_ASM"
-make="make -f $TRAVIS_BUILD_DIR/src/Makefile $f"
+export EXTRA_CPPFLAGS="-DUCL_NO_ASM"
+case $BUILD_METHOD in
+*sanitize) case $CC in gcc*) export EXTRA_LDFLAGS="-fuse-ld=gold" ;; esac ;;
+*valgrind) export EXTRA_CPPFLAGS="$EXTRA_CPPFLAGS -DWITH_VALGRIND" ;;
+esac
+make="make -f $TRAVIS_BUILD_DIR/src/Makefile"
 if test "X$ALLOW_FAIL" = "X1"; then
     echo "ALLOW_FAIL=$ALLOW_FAIL"
     set +e
 fi
 case $BUILD_METHOD in
-debug)
+debug | debug+valgrind)
     $make USE_DEBUG=1 ;;
 debug+sanitize)
     $make USE_DEBUG=1 USE_SANITIZE=1 ;;
-release)
+release | release+valgrind | valgrind)
     $make ;;
 sanitize)
     $make USE_SANITIZE=1 ;;
@@ -111,6 +127,9 @@ if test "X$TRAVIS_OS_NAME" = "Xosx"; then
     checksum=true # TODO: travis-osx does not have md5sum and friends?
 fi
 upx="$PWD/upx.out"
+case $BUILD_METHOD in
+*valgrind) upx="valgrind $upx" ;;
+esac
 upx_391=false
 if test "X$TRAVIS_OS_NAME" = "Xlinux"; then
     cp "$TRAVIS_BUILD_DIR/deps/upx-testsuite/files/packed/amd64-linux.elf/upx-3.91" upx391.out