diff --git a/.circle.yml b/.circle.yml
index 47058ac3..00f679d6 100644
--- a/.circle.yml
+++ b/.circle.yml
@@ -8,7 +8,6 @@ branches:
 
 machine:
   environment:
-    TRAVIS_BUILD_DIR: $HOME/upx
     TRAVIS_OS_NAME: linux
     C: gcc-4.8-m64
     B: release
@@ -20,14 +19,14 @@ checkout:
 
 dependencies:
   pre:
-    - mkdir -p $TRAVIS_BUILD_DIR/deps
-    - cd $TRAVIS_BUILD_DIR/deps && wget --no-check-certificate -q -O - https://download.freenas.org/distfiles/ucl-1.03.tar.gz | tar -xz
-    - cd $TRAVIS_BUILD_DIR/deps && git clone https://github.com/upx/upx-testsuite
+    - mkdir -p ../deps
+    - cd ../deps && wget --no-check-certificate -q -O - https://download.freenas.org/distfiles/ucl-1.03.tar.gz | tar -xz
+    - cd ../deps && git clone https://github.com/upx/upx-testsuite
   override:
-    - bash $TRAVIS_BUILD_DIR/.github/travis_build.sh
+    - bash ./.github/travis_build.sh
 
 test:
   override:
-    - bash $TRAVIS_BUILD_DIR/.github/travis_testsuite.sh
+    - bash ./.github/travis_testsuite.sh
 
 # vim:set ts=2 sw=2 et:
diff --git a/.github/travis_build.sh b/.github/travis_build.sh
index b3d38eca..644b9e01 100644
--- a/.github/travis_build.sh
+++ b/.github/travis_build.sh
@@ -5,10 +5,9 @@ set -e; set -o pipefail
 # Support for Travis CI -- https://travis-ci.org/upx/upx/builds
 # Copyright (C) Markus Franz Xaver Johannes Oberhumer
 
-source "$TRAVIS_BUILD_DIR/.github/travis_init.sh" || exit 1
+source ./.github/travis_init.sh || exit 1
 
 echo "BUILD_METHOD='$BUILD_METHOD'"
-echo "BUILD_DIR='$BUILD_DIR'"
 echo "UPX_UCLDIR='$UPX_UCLDIR'"
 echo "CC='$CC'"
 echo "CXX='$CXX'"
@@ -18,17 +17,20 @@ echo "CXXFLAGS='$CXXFLAGS'"
 echo "LDFLAGS='$LDFLAGS'"
 echo "LIBS='$LIBS'"
 echo "SCAN_BUILD='$SCAN_BUILD'"
-#env | LC_ALL=C sort
+##env | LC_ALL=C sort
 
 echo "$CC --version"; $CC --version
 echo "$CXX --version"; $CXX --version
 
 # whitespace
-if test "$TRAVIS_OS_NAME" = "linux"; then
+if [[ $TRAVIS_OS_NAME == linux ]]; then
+cd $upx_SRCDIR || exit 1
 echo "Checking source code for whitespace violations..."
 find . \
     -type d -name '.git' -prune -o \
-    -type d -name 'deps' -prune -o \
+    -type d -name '.hg' -prune -o \
+    -type d -name 'build' -prune -o \
+    -type d -name 'tmp' -prune -o \
     -type f -iname '*.bat' -prune -o \
     -type f -iname '*.exe' -prune -o \
     -type f -iname '*.pdf' -prune -o \
@@ -43,7 +45,7 @@ xargs -0r perl -n -e '
     }
     if (m,\t,) {
        if ($ARGV =~ m,(^|/)\.gitmodules$,) { }
-       elsif ($ARGV =~ m,(^|/)make(file|vars),i) { }
+       elsif ($ARGV =~ m,(^|/)m?make(file|vars),i) { }
        elsif ($ARGV =~ m,/tmp/.*\.(disasm|dump)$,) { }
        elsif ($ARGV =~ m,/src/stub/src/arch/.*\.S$,) { }
        else { print "ERROR: hard TAB detected $ARGV: $_"; exit(1); }
@@ -58,38 +60,42 @@ set -x
 # build UCL
 #
 
-cd /; cd "$UPX_UCLDIR" || exit 1
-./configure --enable-static --disable-shared --disable-asm
+cd $ucl_BUILDDIR || exit 1
+if [[ ! -f config.status ]]; then
+$ucl_SRCDIR/configure --enable-static --disable-shared --disable-asm
+fi
 make
 
 #
 # build UPX
 #
 
-cd /; cd "$BUILD_DIR" || exit 1
-make="make -f $TRAVIS_BUILD_DIR/src/Makefile"
-export EXTRA_CPPFLAGS="-DUCL_NO_ASM"
-case $BUILD_METHOD in
-    debug | debug+* | *+debug | *+debug+*)
-       make="$make USE_DEBUG=1" ;;
+cd $upx_BUILDDIR || exit 1
+make="make -f $upx_SRCDIR/src/Makefile"
+EXTRA_CPPFLAGS="$EXTRA_CPPFLAGS -DUCL_NO_ASM"
+EXTRA_LDFLAGS="$EXTRA_LDFLAGS -L$ucl_BUILDDIR/src/.libs"
+case $BUILD_METHOD in coverage | coverage+* | *+coverage | *+coverage+*)
+    EXTRA_CXXFLAGS="$EXTRA_CXXFLAGS -fprofile-arcs -ftest-coverage"
+    EXTRA_LDFLAGS="$EXTRA_LDFLAGS -fprofile-arcs -ftest-coverage" ;;
 esac
-case $BUILD_METHOD in
-    sanitize | sanitize+* | *+sanitize | *+sanitize+*)
-        case $TRAVIS_OS_NAME-$CC in linux-gcc*) export EXTRA_LDFLAGS="-fuse-ld=gold" ;; esac
-        make="$make USE_SANITIZE=1" ;;
+case $BUILD_METHOD in debug | debug+* | *+debug | *+debug+*)
+    make="$make USE_DEBUG=1" ;;
 esac
-case $BUILD_METHOD in
-    scan-build | scan-build+* | *+scan-build | *+scan-build+*)
-        make="$SCAN_BUILD $make" ;;
+case $BUILD_METHOD in sanitize | sanitize+* | *+sanitize | *+sanitize+*)
+    case $TRAVIS_OS_NAME-$CC in linux-gcc*) EXTRA_LDFLAGS="$EXTRA_LDFLAGS -fuse-ld=gold" ;; esac
+    make="$make USE_SANITIZE=1" ;;
 esac
-case $BUILD_METHOD in
-    valgrind | valgrind+* | *+valgrind | *+valgrind+*)
-        export EXTRA_CPPFLAGS="$EXTRA_CPPFLAGS -DWITH_VALGRIND" ;;
+case $BUILD_METHOD in scan-build | scan-build+* | *+scan-build | *+scan-build+*)
+    make="$SCAN_BUILD $make" ;;
 esac
-if test "$ALLOW_FAIL" = "1"; then
+case $BUILD_METHOD in valgrind | valgrind+* | *+valgrind | *+valgrind+*)
+    EXTRA_CPPFLAGS="$EXTRA_CPPFLAGS -DWITH_VALGRIND" ;;
+esac
+if [[ $ALLOW_FAIL == 1 ]]; then
     echo "ALLOW_FAIL=$ALLOW_FAIL"
     set +e
 fi
+export EXTRA_CPPFLAGS EXTRA_CXXFLAGS EXTRA_LDFLAGS
 
 $make
 
diff --git a/.github/travis_init.sh b/.github/travis_init.sh
index bc873df3..8777487d 100644
--- a/.github/travis_init.sh
+++ b/.github/travis_init.sh
@@ -3,17 +3,11 @@
 # Support for Travis CI -- https://travis-ci.org/upx/upx/builds
 # Copyright (C) Markus Franz Xaver Johannes Oberhumer
 
+#set -x # debug
 umask 022
-cd /; cd "$TRAVIS_BUILD_DIR" || exit 1
-
-if test "X$C" = "X"; then C=gcc; fi
-BUILD_DIR="$TRAVIS_BUILD_DIR/build/$C"
-mkdir -p "$BUILD_DIR"
-
-if test "X$B" = "X"; then B=release; fi
-BUILD_METHOD="$B"
 
 CC=false CXX=false SCAN_BUILD=false
+[[ -z $C ]] && C=gcc
 case $C in
     clang | clang-m?? | clang-3.4-m?? | clang-[678][0-9][0-9]-m??)
         # standard system compiler
@@ -37,4 +31,32 @@ case $C in
 esac
 export CC CXX
 
-export UPX_UCLDIR="$TRAVIS_BUILD_DIR/deps/ucl-1.03"
+[[ -z $B ]] && B=release
+BUILD_METHOD="$B"
+
+# dirs
+[[ -z $upx_SRCDIR ]] && upx_SRCDIR="$PWD"
+[[ -z $ucl_SRCDIR ]] && ucl_SRCDIR="$PWD/../deps/ucl-1.03"
+[[ -z $upx_testsuite_SRCDIR ]] && upx_testsuite_SRCDIR="$PWD/../deps/upx-testsuite"
+
+[[ -z $tmake_top_builddir ]] && tmake_top_builddir="$PWD/../build"
+[[ -z $tmake_top_bdir ]] && tmake_top_bdir="$tmake_top_builddir/$C/$B"
+upx_BUILDDIR="$tmake_top_bdir/upx"
+ucl_BUILDDIR="$tmake_top_bdir/ucl-1.03"
+upx_testsuite_BUILDDIR="$tmake_top_bdir/upx-testsuite"
+# tools
+lcov_OUTPUTDIR="$tmake_top_bdir/.lcov-results"
+
+mkdir -p -v $upx_BUILDDIR $ucl_BUILDDIR $upx_testsuite_BUILDDIR
+[[ -d $tmake_top_bdir/.mfxnobackup ]] || echo "timestamp" > $tmake_top_bdir/.mfxnobackup
+
+export UPX_UCLDIR="$ucl_SRCDIR"
+
+# check dirs
+cd / && cd $ucl_BUILDDIR || exit 1
+cd / && cd $ucl_SRCDIR || exit 1
+cd / && cd $upx_testsuite_BUILDDIR || exit 1
+cd / && cd $upx_testsuite_SRCDIR || exit 1
+cd / && cd $upx_BUILDDIR || exit 1
+# enter srcdir
+cd / && cd $upx_SRCDIR || exit 1
diff --git a/.github/travis_testsuite.sh b/.github/travis_testsuite.sh
index 2db76ee9..bcaa0703 100644
--- a/.github/travis_testsuite.sh
+++ b/.github/travis_testsuite.sh
@@ -5,17 +5,17 @@ set -e; set -o pipefail
 # Support for Travis CI -- https://travis-ci.org/upx/upx/builds
 # Copyright (C) Markus Franz Xaver Johannes Oberhumer
 
-source "$TRAVIS_BUILD_DIR/.github/travis_init.sh" || exit 1
+source ./.github/travis_init.sh || exit 1
 
 set -x
 
-cd /; cd "$BUILD_DIR" || exit 1
-if test "$ALLOW_FAIL" = "1"; then
+cd $upx_BUILDDIR || exit 1
+if [[ $ALLOW_FAIL == 1 ]]; then
     echo "ALLOW_FAIL=$ALLOW_FAIL"
     set +e
-    if ! test -x $PWD/upx.out; then exit 0; fi
+    if [[ ! -x $PWD/upx.out ]]; then exit 0; fi
 fi
-if ! test -x $PWD/upx.out; then exit 1; fi
+if [[ ! -x $PWD/upx.out ]]; then exit 1; fi
 
 #
 # very first version of the upx-testsuite
@@ -24,61 +24,96 @@ if ! test -x $PWD/upx.out; then exit 1; fi
 exit_code=0
 
 sha256sum=sha256sum
-if test "$TRAVIS_OS_NAME" = "osx"; then
+if [[ $TRAVIS_OS_NAME == osx ]]; then
     sha256sum=gsha256sum # brew install coreutils
 fi
-upx="$PWD/upx.out"
-case $BUILD_METHOD in
-    valgrind | valgrind+* | *+valgrind | *+valgrind+*)
-        upx="valgrind --leak-check=full --show-reachable=yes $upx" ;;
+upx=$PWD/upx.out
+case $BUILD_METHOD in valgrind | valgrind+* | *+valgrind | *+valgrind+*)
+    upx="valgrind --leak-check=full --show-reachable=yes $upx" ;;
 esac
-upx_391=false
-if test "$TRAVIS_OS_NAME" = "linux"; then
-    cp "$TRAVIS_BUILD_DIR/deps/upx-testsuite/files/packed/amd64-linux.elf/upx-3.91" upx391.out
-    upx_391="$PWD/upx391.out"
+upx_391=
+if [[ $TRAVIS_OS_NAME == linux ]]; then
+    rm -f upx391.out
+    cp $upx_testsuite_SRCDIR/files/packed/amd64-linux.elf/upx-3.91 upx391.out
+    upx_391="$PWD/upx391.out --fake-stub-version=3.92 --fake-stub-year=2016"
 fi
 
+case $BUILD_METHOD in coverage | coverage+* | *+coverage | *+coverage+*)
+    lcov -d $upx_BUILDDIR --zerocounters ;;
+esac
+
 $upx --version
 $upx --help
 
-cd /; cd "$TRAVIS_BUILD_DIR/deps/upx-testsuite/files" || exit 1
+cd $upx_testsuite_SRCDIR/files || exit 1
 ls -l            packed/*/upx-3.91*
 $upx -l          packed/*/upx-3.91*
 $upx --file-info packed/*/upx-3.91*
 $upx -t          packed/*/upx-3.91*
-for f in packed/*/upx-3.91*; do
+cd $upx_testsuite_BUILDDIR || exit 1
+rm -rf ./t
+for f in $upx_testsuite_SRCDIR/files/packed/*/upx-3.91*; do
     echo "===== $f"
-    if test "$TRAVIS_OS_NAME" = "linux"; then
-        $upx_391 -d $f -o v391.tmp
-        $upx     -d $f -o v392.tmp
-        $sha256sum v391.tmp v392.tmp
-        cmp -s v391.tmp v392.tmp
-        $upx_391 --lzma --fake-stub-version=3.92 --fake-stub-year=2016 v391.tmp -o v391_packed.tmp
-        $upx     --lzma                                                v392.tmp -o v392_packed.tmp
-        $sha256sum v391_packed.tmp v392_packed.tmp
+    mkdir -p ./t
+    if [[ -n $upx_391 ]]; then
+        $upx_391 -d $f -o t/v391
+        $upx     -d $f -o t/v392
+        $sha256sum t/v391 t/v392
+        cmp -s t/v391 t/v392
+        $upx_391 --lzma t/v391 -o t/v391_packed
+        $upx     --lzma t/v392 -o t/v392_packed
+        $sha256sum t/v391_packed t/v392_packed
     else
-        $upx     -d $f -o v392.tmp
-        $sha256sum v392.tmp
-        $upx     --lzma                                                v392.tmp -o v392_packed.tmp
-        $sha256sum v392_packed.tmp
+        $upx     -d $f -o t/v392
+        $sha256sum t/v392
+        $upx     --lzma t/v392 -o t/v392_packed
+        $sha256sum t/v392_packed
     fi
-    $upx -d v392_packed.tmp -o v392_decompressed.tmp
+    $upx -d t/v392_packed -o t/v392_decompressed
     # after the first compression+decompression step the exe should be
     # canonicalized so that further compression+decompression runs
     # should yield identical results
-    if ! cmp -s v392.tmp v392_decompressed.tmp; then
+    if ! cmp -s t/v392 t/v392_decompressed; then
         # UPX 3.91 and 3.92 differ; run one more compression+decompression
-        ls -l v392.tmp v392_decompressed.tmp
+        ls -l t/v392 t/v392_decompressed
         echo "UPX-WARNING: $f"
-        $upx v392_decompressed.tmp -o v392_packed_2.tmp
-        $upx -d v392_packed_2.tmp -o v392_decompressed_2.tmp
-        if ! cmp -s v392_decompressed.tmp v392_decompressed_2.tmp; then
-            ls -l v392_decompressed.tmp v392_decompressed_2.tmp
+        $upx t/v392_decompressed -o t/v392_packed_2
+        $upx -d t/v392_packed_2 -o t/v392_decompressed_2
+        if ! cmp -s t/v392_decompressed t/v392_decompressed_2; then
+            ls -l t/v392_decompressed t/v392_decompressed_2
             echo "UPX-ERROR: $f"
             exit_code=1
         fi
     fi
-    rm *.tmp
+    #
+    u391=$upx_391
+    [[ -z $u391 ]] && u391=true
+    x=t/v392
+    $u391 --lzma -2 $x -o t/x_v391_lzma2
+    $upx  --lzma -2 $x -o t/x_v392_lzma2
+    $u391 --lzma -2 --small $x -o t/x_v391_lzma2_small
+    $upx  --lzma -2 --small $x -o t/x_v392_lzma2_small
+    $u391 --lzma -2 --all-filters $x -o t/x_v391_lzma2_small_all_filters
+    $upx  --lzma -2 --all-filters $x -o t/x_v392_lzma2_small_all_filters
+    ls -l      t/x_v*
+    $upx -t    t/x_v*
+    $sha256sum t/x_v*
+    #
+    rm -rf ./t
 done
 
+case $BUILD_METHOD in coverage | coverage+* | *+coverage | *+coverage+*)
+    if [[ -n $TRAVIS_JOB_ID ]]; then
+        cd $upx_SRCDIR || exit 1
+        coveralls -b $upx_BUILDDIR --gcov-options '\-lp' || true
+    else
+        cd $upx_BUILDDIR || exit 1
+        mkdir -p $lcov_OUTPUTDIR
+        lcov -d . --capture -o $lcov_OUTPUTDIR/upx.info
+        cd $lcov_OUTPUTDIR || exit 1
+        genhtml upx.info
+    fi
+    ;;
+esac
+
 exit $exit_code
diff --git a/.gitignore b/.gitignore
index 2ba7c78b..81bf8c04 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,6 +5,8 @@
 /maint*
 
 .depend
+GNUmakefile
+MMakefile
 Makevars.local*
 
 *.a
@@ -21,8 +23,6 @@ doc/*.man
 doc/*.ps
 doc/*.tex
 
-src/GNUmakefile
-src/MMakefile
 src/compress_nrv*
 src/*.mft
 src/*.rc
diff --git a/.travis.yml b/.travis.yml
index 79dd523c..03a868b5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,7 +5,9 @@ sudo: false
 language: cpp
 
 notifications:
-  email: false
+  email:
+    on_success: never
+    on_failure: change
 
 branches:
   only:
@@ -45,6 +47,10 @@ matrix:
     - os: linux
       compiler: gcc
       env: C=gcc-4.6-m64
+    - os: linux
+      compiler: gcc
+      env: C=gcc-4.6-m64 B=coverage
+      addons: { apt: { packages: [ lcov ] } }
     - os: linux
       compiler: gcc
       env: C=gcc-5-m32
@@ -80,7 +86,7 @@ matrix:
     - os: linux
       compiler: gcc
       env: C=gcc-6-m64 B=valgrind
-      addons: { apt: { sources: *S, packages: [ "g++-6", "valgrind" ] } }
+      addons: { apt: { sources: *S, packages: [ "g++-6", valgrind ] } }
     - os: linux
       compiler: clang
       env: C=clang-3.4-m32
@@ -164,16 +170,26 @@ matrix:
       osx_image: xcode8
 
 install:
-  - umask 022; DEPS_DIR="$TRAVIS_BUILD_DIR/deps"; mkdir -p "$DEPS_DIR" && cd "$DEPS_DIR"
-  - travis_retry wget --no-check-certificate -q -O - https://download.freenas.org/distfiles/ucl-1.03.tar.gz | tar -xz
-  - travis_retry git clone https://github.com/upx/upx-testsuite
+  - umask 022; cd $TRAVIS_BUILD_DIR && mkdir -p ../deps
+  - cd ../deps && travis_retry wget --no-check-certificate -q -O - https://download.freenas.org/distfiles/ucl-1.03.tar.gz | tar -xz
+  - cd ../deps && travis_retry git clone https://github.com/upx/upx-testsuite
   - |
-    if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then
+    cd /
+    if [[ $TRAVIS_OS_NAME == linux ]]; then
+      case $B in coverage | coverage+* | *+coverage | *+coverage+*)
+        travis_retry pip install --user cpp-coveralls ;;
+      esac
+    fi
+    if [[ $TRAVIS_OS_NAME == osx ]]; then
       if ! gsha256sum </bin/sh >/dev/null 2>/dev/null; then travis_retry brew install coreutils; fi
+      case $B in coverage | coverage+* | *+coverage | *+coverage+*)
+        travis_retry brew install lcov
+        travis_retry pip install --user cpp-coveralls ;;
+      esac
     fi
 
 script:
-  - bash $TRAVIS_BUILD_DIR/.github/travis_build.sh
-  - bash $TRAVIS_BUILD_DIR/.github/travis_testsuite.sh
+  - cd $TRAVIS_BUILD_DIR && bash ./.github/travis_build.sh
+  - cd $TRAVIS_BUILD_DIR && bash ./.github/travis_testsuite.sh
 
 # vim:set ts=2 sw=2 et:
diff --git a/src/Makefile b/src/Makefile
index d4577c51..69a9f919 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -20,7 +20,7 @@ endif
 
 .SUFFIXES:
 export SHELL = /bin/sh
-override e = $($1) $(EXTRA_$1) $(upx_$1) $($(basename $(notdir $@)).$1)
+override e = $($1) $(EXTRA_$1) $(upx_$1) $(upx_EXTRA_$1) $($(basename $(notdir $@)).$1)
 
 ifneq ($(findstring $(firstword $(MAKE_VERSION)),3.77 3.78 3.78.1 3.79 3.79.1 3.80),)
 $(error GNU make 3.81 or better is required)
@@ -69,7 +69,6 @@ ifdef USE_DEBUG
 CXXFLAGS += -O0 -g
 else
 CXXFLAGS += -O2
-LDFLAGS += -s
 endif
 # protect against security threats caused by misguided C++ compiler "optimizations"
 ifeq ($(findstring clang,$(CXX)),)