shithub: libvpx

--- a/README

+++ b/README

@@ -45,7 +45,16 @@

   used to get a list of supported options:

     $ ../libvpx/configure --help

-  4. Cross development

+  4. Compiler analyzers

+  Compilers have added sanitizers which instrument binaries with information

+  about address calculation, memory usage, threading, undefined behavior, and

+  other common errors. To simplify building libvpx with some of these features

+  use tools/set_analyzer_env.sh before running configure. It will set the

+  compiler and necessary flags for building as well as environment variables

+  read by the analyzer when testing the binaries.

+    $ source ../libvpx/tools/set_analyzer_env.sh address

+  5. Cross development

   For cross development, the most notable option is the --target option. The

   most up-to-date list of supported targets can be found at the bottom of the

   --help output of the configure script. As of this writing, the list of

@@ -127,7 +136,7 @@

   environment variables: CC, AR, LD, AS, STRIP, NM. Additional flags can be

   passed to these executables with CFLAGS, LDFLAGS, and ASFLAGS.

-  5. Configuration errors

+  6. Configuration errors

   If the configuration step fails, the first step is to look in the error log.

   This defaults to config.log. This should give a good indication of what went

   wrong. If not, contact us for support.

--- /dev/null

+++ b/tools/set_analyzer_env.sh

@@ -1,0 +1,120 @@

+##  Copyright (c) 2018 The WebM project authors. All Rights Reserved.

+##

+##  Use of this source code is governed by a BSD-style license

+##  that can be found in the LICENSE file in the root of the source

+##  tree. An additional intellectual property rights grant can be found

+##  in the file PATENTS.  All contributing project authors may

+##  be found in the AUTHORS file in the root of the source tree.

+##

+##  Sourcing this file sets environment variables to simplify setting up

+##  sanitizer builds and testing.

+sanitizer="${1}"

+case "${sanitizer}" in

+  address) ;;

+  integer) ;;

+  memory) ;;

+  thread) ;;

+  undefined) ;;

+  clear)

+    echo "Clearing environment:"

+    set -x

+    unset CC CXX LD

+    unset CFLAGS CXXFLAGS LDFLAGS

+    unset ASAN_OPTIONS MSAN_OPTIONS TSAN_OPTIONS UBSAN_OPTIONS

+    set +x

+    return

+    ;;

+  *)

+    echo "Usage: source set_analyzer_env.sh [<sanitizer>|clear]"

+    echo "  Supported sanitizers:"

+    echo "    address integer memory thread undefined"

+    return 1

+    ;;

+esac

+if [ ! $(which clang) ]; then

+  # TODO(johannkoenig): Support gcc analyzers.

+  echo "ERROR: 'clang' must be in your PATH"

+  return 1

+fi

+# Warnings.

+if [ "${sanitizer}" = "undefined" -o "${sanitizer}" = "integer" ]; then

+  echo "WARNING: When building the ${sanitizer} sanitizer for 32 bit targets"

+  echo "you must run:"

+  echo "export LDFLAGS=\"\${LDFLAGS} --rtlib=compiler-rt -lgcc_s\""

+  echo "See http://llvm.org/bugs/show_bug.cgi?id=17693 for details."

+fi

+if [ "${sanitizer}" = "undefined" ]; then

+  major_version=$(clang --version | head -n 1 \

+    | grep -o -E "[[:digit:]]\.[[:digit:]]\.[[:digit:]]" | cut -f1 -d.)

+  if [ ${major_version} -eq 5 ]; then

+    echo "WARNING: clang v5 has a problem with vp9 x86_64 high bit depth"

+    echo "configurations. It can take ~40 minutes to compile"

+    echo "vpx_dsp/x86/fwd_txfm_sse2.c"

+    echo "clang v4 did not have this issue."

+  fi

+fi

+echo "It is recommended to configure with '--enable-debug' to improve stack"

+echo "traces. On mac builds, run 'dysmutil' on the output binaries (vpxenc,"

+echo "test_libvpx, etc) to link the stack traces to source code lines."

+# Build configuration.

+cflags="-fsanitize=${sanitizer}"

+ldflags="-fsanitize=${sanitizer}"

+# http://code.google.com/p/webm/issues/detail?id=570

+cflags="${cflags} -fno-strict-aliasing"

+# Useful backtraces.

+cflags="${cflags} -fno-omit-frame-pointer"

+# Exact backtraces.

+cflags="${cflags} -fno-optimize-sibling-calls"

+set -x

+export CC="clang"

+export CXX="clang++"

+export LD="clang++"

+export CFLAGS="${cflags}"

+export CXXFLAGS="${cflags}"

+export LDFLAGS="${ldflags}"

+set +x

+# Execution configuration.

+sanitizer_options=""

+sanitizer_options="${sanitizer_options}:handle_segv=1"

+sanitizer_options="${sanitizer_options}:handle_abort=1"

+sanitizer_options="${sanitizer_options}:handle_sigfpe=1"

+sanitizer_options="${sanitizer_options}:fast_unwind_on_fatal=1"

+sanitizer_options="${sanitizer_options}:allocator_may_return_null=1"

+case "${sanitizer}" in

+  address)

+    sanitizer_options="${sanitizer_options}:detect_stack_use_after_return=1"

+    sanitizer_options="${sanitizer_options}:max_uar_stack_size_log=17"

+    set -x

+    export ASAN_OPTIONS="${sanitizer_options}"

+    set +x

+    ;;

+  memory)

+    set -x

+    export MSAN_OPTIONS="${sanitizer_options}"

+    set +x

+    ;;

+  thread)

+    # The thread sanitizer uses an entirely independent set of options.

+    set -x

+    export TSAN_OPTIONS="halt_on_error=1"

+    set +x

+    ;;

+  undefined|integer)

+    sanitizer_options="${sanitizer_options}:print_stacktrace=1"

+    set -x

+    export UBSAN_OPTIONS="${sanitizer_options}"

+    set +x

+    ;;

+esac