at workaround for throw_out_of_range_fmt

remove inadvertent change

also dump glibcxx symbols on circle

add glibc_workaround.cpp if option is chosen

This reverts commit 751d9bff1672f6b8cbd2b5ebe2eb460223746806.

add script that asserts on expected symbols

check symbols for all modes, only error if symbols exist + ENABLE_GLIBC_WORKAROUND

.travis.yml

@@ -33,7 +33,7 @@ matrix:
     - os: linux
       sudo: false
       compiler: ": clang"
-      env: JOBS=8 CXX="ccache clang++-3.9 -Qunused-arguments" CC="clang-3.9" TRIGGER=true
+      env: JOBS=8 CXX="ccache clang++-3.9 -Qunused-arguments" CC="clang-3.9" ENABLE_GLIBC_WORKAROUND=True TRIGGER=true
       addons:
         apt:
           sources: [ 'ubuntu-toolchain-r-test']
@@ -95,7 +95,7 @@ before_script:
 
 script:
  - export SCONSFLAGS='--debug=time'
- - configure BENCHMARK=${BENCH}
+ - configure BENCHMARK=${BENCH} ENABLE_GLIBC_WORKAROUND=${ENABLE_GLIBC_WORKAROUND:-False}
  - cat config.log
  # we limit the `make` to 40 min
  # to ensure that slow builds still upload their
@@ -108,4 +108,8 @@ script:
  # we allow visual failures with g++ for now: https://github.com/mapnik/mapnik/issues/3567
  - if [[ ${RESULT} != 0 ]] && [[ ${CXX} =~ 'clang++' ]]; then false; fi;
  - enabled ${COVERAGE} coverage
- - enabled ${BENCH} make bench
+ - enabled ${BENCH} make bench
+ - ./scripts/check_glibcxx.sh
+
+after_success:
+ - enabled ${TRIGGER} trigger_downstream

SConstruct

@@ -308,6 +308,7 @@ opts.AddVariables(
     BoolVariable('USE_CONFIG', "Use SCons user '%s' file (will also write variables after successful configuration)", 'True'),
     BoolVariable('NO_ATEXIT', 'Will prevent Singletons from being deleted atexit of main thread', 'False'),
     BoolVariable('NO_DLCLOSE', 'Will prevent plugins from being unloaded', 'False'),
+    BoolVariable('ENABLE_GLIBC_WORKAROUND', "Workaround known GLIBC symbol exports to allow building against libstdc++-4.8 without binaries needing throw_out_of_range_fmt", 'False'),
     # http://www.scons.org/wiki/GoFastButton
     # http://stackoverflow.com/questions/1318863/how-to-optimize-an-scons-script
     BoolVariable('FAST', "Make SCons faster at the cost of less precise dependency tracking", 'False'),
@@ -1872,6 +1873,9 @@ if not preconfigured:
         if env['NO_DLCLOSE'] or env['COVERAGE']:
             env.Append(CPPDEFINES = '-DMAPNIK_NO_DLCLOSE')
 
+        if env['ENABLE_GLIBC_WORKAROUND']:
+            env.Append(CPPDEFINES = '-DMAPNIK_ENABLE_GLIBC_WORKAROUND')
+
         # Mac OSX (Darwin) special settings
         if env['PLATFORM'] == 'Darwin':
             pthread = ''

circle.yml

@@ -32,6 +32,7 @@ database:
     - ./.mason/mason link clang++ ${LLVM_VERSION}
     - ./configure CC="$(pwd)/mason_packages/.link/bin/clang" CXX="$(pwd)/mason_packages/.link/bin/ccache $(pwd)/mason_packages/.link/bin/clang++ -Qunused-arguments"
     - make
+    - nm src/libmapnik* | grep "GLIBCXX_3.4.2[0-9]" || true
   override:
     - psql -c 'create database template_postgis;'
     - psql -c 'create extension postgis;' -d template_postgis

scripts/check_glibcxx.sh

@@ -0,0 +1,36 @@
+#!/bin/bash
+
+set -eu
+set -o pipefail
+shopt -s nullglob
+
+: '
+
+Ensure no GLIBCXX_3.4.2x symbols are present in the binary
+if ENABLE_GLIBC_WORKAROUND is set.
+
+If symbols >= 3.4.20 then it means the binaries would not run on ubuntu trusty without upgrading libstdc++
+
+'
+
+FINAL_RETURN_CODE=0
+
+function check() {
+    local RESULT=0
+    nm ${1} | grep "GLIBCXX_3.4.2[0-9]" > /tmp/out.txt || RESULT=$?
+    if [[ ${RESULT} != 0 ]]; then
+        echo "Success: GLIBCXX_3.4.2[0-9] symbols not present in binary (as expected)"
+    else
+        echo "$(cat /tmp/out.txt | c++filt)"
+        if [[ ${ENABLE_GLIBC_WORKAROUND:-false} == true ]]; then
+            FINAL_RETURN_CODE=1
+        fi
+    fi
+}
+
+for i in src/libmapnik*; do
+    echo "checking $i"
+    check $i
+done
+
+exit ${FINAL_RETURN_CODE}

src/build.py

@@ -307,6 +307,13 @@ cairo/process_markers_symbolizer.cpp
 cairo/process_group_symbolizer.cpp
 """)
 
+if env['ENABLE_GLIBC_WORKAROUND']:
+    source += Split(
+            """
+            glibc_workaround.cpp
+            """
+        )
+
 if env['HAS_CAIRO']:
     lib_env.AppendUnique(LIBPATH=env['CAIRO_LIBPATHS'])
     lib_env.Append(CPPDEFINES = '-DHAVE_CAIRO')

src/font_engine_freetype.cpp

@@ -53,6 +53,7 @@ namespace mapnik
 {
 template class MAPNIK_DECL singleton<freetype_engine, CreateUsingNew>;
 
+
 bool freetype_engine::is_font_file(std::string const& file_name)
 {
     // only accept files that will be matched by freetype2's `figurefiletype()`

src/glibc_workaround.cpp

@@ -0,0 +1,48 @@
+/*****************************************************************************
+ *
+ * This file is part of Mapnik (c++ mapping toolkit)
+ *
+ * Copyright (C) 2017 Artem Pavlenko
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ *****************************************************************************/
+
+#ifdef __linux__
+
+#ifdef MAPNIK_ENABLE_GLIBC_WORKAROUND
+
+#include <stdexcept>
+
+// https://github.com/bitcoin/bitcoin/pull/4042
+// allows building against libstdc++-dev-4.9 while avoiding
+// GLIBCXX_3.4.20 dep
+// This is needed because libstdc++ itself uses this API - its not
+// just an issue of your code using it, ughhh
+
+namespace std
+{
+
+void __throw_out_of_range_fmt(const char *, ...) __attribute__((__noreturn__));
+void __throw_out_of_range_fmt(const char *err, ...)
+{
+    // Safe and over-simplified version. Ignore the format and print it as-is.
+    __throw_out_of_range(err);
+}
+}
+
+#endif // MAPNIK_ENABLE_GLIBC_WORKAROUND
+
+#endif // __linux__