Merge pull request #9835 from Chocobo1/cppver

Implement proper C++11 mode detection

.travis.yml

@@ -158,7 +158,9 @@ script:
       if [ "$TRAVIS_OS_NAME" = "osx" ]; then
         # For some reason for RC_1_1 we need to also specify the OpenSSL compiler/linker flags
         # Homebrew doesn't symlink OpenSSL for security reasons
-        ./bootstrap.sh && ./configure $qbtconf CXXFLAGS="$(PKG_CONFIG_PATH="/usr/local/opt/openssl/lib/pkgconfig:$PKG_CONFIG_PATH" pkg-config --cflags openssl)" LDFLAGS="$(PKG_CONFIG_PATH="/usr/local/opt/openssl/lib/pkgconfig:$PKG_CONFIG_PATH" pkg-config --libs openssl)"
+        ./bootstrap.sh
+        ./configure $qbtconf CXXFLAGS="$CXXFLAGS $(PKG_CONFIG_PATH="/usr/local/opt/openssl/lib/pkgconfig:$PKG_CONFIG_PATH" pkg-config --cflags openssl) -std=c++14" \
+          LDFLAGS="$LDFLAGS $(PKG_CONFIG_PATH="/usr/local/opt/openssl/lib/pkgconfig:$PKG_CONFIG_PATH" pkg-config --libs openssl)"
         sed -i "" -e "s/^\(CC.*&&\).*$/\1 $CC/" src/Makefile  # workaround for Qt & ccache: https://bugreports.qt.io/browse/QTBUG-31034
         sed -i "" -e "s/^\(CXX.*&&\).*$/\1 $CXX/" src/Makefile
         sed -i "" -e 's/^\(CXXFLAGS.*\)$/\1 -Wno-unused-local-typedefs -Wno-inconsistent-missing-override/' src/Makefile

configure

@@ -626,7 +626,6 @@ am__nodep
 AMDEPBACKSLASH
 AMDEP_FALSE
 AMDEP_TRUE
-am__quote
 am__include
 DEPDIR
 am__untar
@@ -709,7 +708,8 @@ PACKAGE_VERSION
 PACKAGE_TARNAME
 PACKAGE_NAME
 PATH_SEPARATOR
-SHELL'
+SHELL
+am__quote'
 ac_subst_files=''
 ac_user_opts='
 enable_option_checking
@@ -3274,7 +3274,7 @@ IFS=$ac_save_IFS
 case $host_os in *\ *) host_os=`echo "$host_os" | sed 's/ /-/g'`;; esac
 
 
-am__api_version='1.15'
+am__api_version='1.16'
 
 # Find a good install program.  We prefer a C program (faster),
 # so one script is as good as another.  But avoid the broken or
@@ -3700,45 +3700,45 @@ DEPDIR="${am__leading_dot}deps"
 
 ac_config_commands="$ac_config_commands depfiles"
 
-
-am_make=${MAKE-make}
-cat > confinc << 'END'
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} supports the include directive" >&5
+$as_echo_n "checking whether ${MAKE-make} supports the include directive... " >&6; }
+cat > confinc.mk << 'END'
 am__doit:
-	@echo this is the am__doit target
+	@echo this is the am__doit target >confinc.out
 .PHONY: am__doit
 END
-# If we don't find an include directive, just comment out the code.
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for style of include used by $am_make" >&5
-$as_echo_n "checking for style of include used by $am_make... " >&6; }
 am__include="#"
 am__quote=
-_am_result=none
-# First try GNU make style include.
-echo "include confinc" > confmf
-# Ignore all kinds of additional output from 'make'.
-case `$am_make -s -f confmf 2> /dev/null` in #(
-*the\ am__doit\ target*)
-  am__include=include
-  am__quote=
-  _am_result=GNU
-  ;;
-esac
-# Now try BSD make style include.
-if test "$am__include" = "#"; then
-   echo '.include "confinc"' > confmf
-   case `$am_make -s -f confmf 2> /dev/null` in #(
-   *the\ am__doit\ target*)
-     am__include=.include
-     am__quote="\""
-     _am_result=BSD
+# BSD make does it like this.
+echo '.include "confinc.mk" # ignored' > confmf.BSD
+# Other make implementations (GNU, Solaris 10, AIX) do it like this.
+echo 'include confinc.mk # ignored' > confmf.GNU
+_am_result=no
+for s in GNU BSD; do
+  { echo "$as_me:$LINENO: ${MAKE-make} -f confmf.$s && cat confinc.out" >&5
+   (${MAKE-make} -f confmf.$s && cat confinc.out) >&5 2>&5
+   ac_status=$?
+   echo "$as_me:$LINENO: \$? = $ac_status" >&5
+   (exit $ac_status); }
+  case $?:`cat confinc.out 2>/dev/null` in #(
+  '0:this is the am__doit target') :
+    case $s in #(
+  BSD) :
+    am__include='.include' am__quote='"' ;; #(
+  *) :
+    am__include='include' am__quote='' ;;
+esac ;; #(
+  *) :
      ;;
-   esac
-fi
-
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $_am_result" >&5
-$as_echo "$_am_result" >&6; }
-rm -f confinc confmf
+esac
+  if test "$am__include" != "#"; then
+    _am_result="yes ($s style)"
+    break
+  fi
+done
+rm -f confinc.* confmf.*
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: ${_am_result}" >&5
+$as_echo "${_am_result}" >&6; }
 
 # Check whether --enable-dependency-tracking was given.
 if test "${enable_dependency_tracking+set}" = set; then :
@@ -3850,8 +3850,8 @@ MAKEINFO=${MAKEINFO-"${am_missing_run}makeinfo"}
 
 # For better backward compatibility.  To be removed once Automake 1.9.x
 # dies out for good.  For more background, see:
-# <http://lists.gnu.org/archive/html/automake/2012-07/msg00001.html>
-# <http://lists.gnu.org/archive/html/automake/2012-07/msg00014.html>
+# <https://lists.gnu.org/archive/html/automake/2012-07/msg00001.html>
+# <https://lists.gnu.org/archive/html/automake/2012-07/msg00014.html>
 mkdir_p='$(MKDIR_P)'
 
 # We need awk for the "check" target (and possibly the TAP driver).  The
@@ -4158,7 +4158,7 @@ END
 Aborting the configuration process, to ensure you take notice of the issue.
 
 You can download and install GNU coreutils to get an 'rm' implementation
-that behaves properly: <http://www.gnu.org/software/coreutils/>.
+that behaves properly: <https://www.gnu.org/software/coreutils/>.
 
 If you want to complete the configuration process using your problematic
 'rm' anyway, export the environment variable ACCEPT_INFERIOR_RM_PROGRAM
@@ -4170,8 +4170,6 @@ END
 fi
 
 
-
-
 # Define --wth-* and --enable-* arguments
 
 
@@ -5497,6 +5495,75 @@ $as_echo "yes" >&6; }
                  LIBS="$zlib_LIBS $LIBS"
 fi
 
+# Check compiler C++11 support
+ac_ext=cpp
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+
+
+_tmp="$CXXFLAGS"
+CXXFLAGS="$CXXFLAGS -std=c++11"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#ifndef __cplusplus
+#error "This is not a C++ compiler"
+#elif __cplusplus < 201103L
+#error "This is not a C++11 compiler"
+#endif
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+
+else
+  as_fn_error $? "A compiler supporting C++11 is required." "$LINENO" 5
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+CXXFLAGS="$_tmp"
+
+_tmp="$CXXFLAGS"
+CXXFLAGS="$CXXFLAGS $libtorrent_CFLAGS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#ifndef __cplusplus
+#error "This is not a C++ compiler"
+#elif __cplusplus < 201103L
+#error "This is not a C++11 compiler"
+#endif
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_cxx_try_compile "$LINENO"; then :
+
+else
+  as_fn_error $? "Compiler is not working in C++11 or later mode.
+    Make sure you use the same C++ mode for qBittorrent and its dependencies.
+    Example: \`CXXFLAGS=\"\$CXXFLAGS -std=c++11\" ./configure\`" "$LINENO" 5
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+CXXFLAGS="$_tmp"
+ac_ext=cpp
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+
 # These are required because autoconf doesn't expand these **particular**
 # vars automatically. And qmake cannot autoexpand them.
 
@@ -6340,7 +6407,7 @@ cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 #
 # INIT-COMMANDS
 #
-AMDEP_TRUE="$AMDEP_TRUE" ac_aux_dir="$ac_aux_dir"
+AMDEP_TRUE="$AMDEP_TRUE" MAKE="${MAKE-make}"
 
 _ACEOF
 
@@ -6785,29 +6852,35 @@ $as_echo "$as_me: executing $ac_file commands" >&6;}
   # Older Autoconf quotes --file arguments for eval, but not when files
   # are listed without --file.  Let's play safe and only enable the eval
   # if we detect the quoting.
-  case $CONFIG_FILES in
-  *\'*) eval set x "$CONFIG_FILES" ;;
-  *)   set x $CONFIG_FILES ;;
-  esac
+  # TODO: see whether this extra hack can be removed once we start
+  # requiring Autoconf 2.70 or later.
+  case $CONFIG_FILES in #(
+  *\'*) :
+    eval set x "$CONFIG_FILES" ;; #(
+  *) :
+    set x $CONFIG_FILES ;; #(
+  *) :
+     ;;
+esac
   shift
-  for mf
+  # Used to flag and report bootstrapping failures.
+  am_rc=0
+  for am_mf
   do
     # Strip MF so we end up with the name of the file.
-    mf=`echo "$mf" | sed -e 's/:.*$//'`
-    # Check whether this is an Automake generated Makefile or not.
-    # We used to match only the files named 'Makefile.in', but
-    # some people rename them; so instead we look at the file content.
-    # Grep'ing the first line is not enough: some people post-process
-    # each Makefile.in and add a new line on top of each file to say so.
-    # Grep'ing the whole file is not good either: AIX grep has a line
+    am_mf=`$as_echo "$am_mf" | sed -e 's/:.*$//'`
+    # Check whether this is an Automake generated Makefile which includes
+    # dependency-tracking related rules and includes.
+    # Grep'ing the whole file directly is not great: AIX grep has a line
     # limit of 2048, but all sed's we know have understand at least 4000.
-    if sed -n 's,^#.*generated by automake.*,X,p' "$mf" | grep X >/dev/null 2>&1; then
-      dirpart=`$as_dirname -- "$mf" ||
-$as_expr X"$mf" : 'X\(.*[^/]\)//*[^/][^/]*/*$' \| \
-	 X"$mf" : 'X\(//\)[^/]' \| \
-	 X"$mf" : 'X\(//\)$' \| \
-	 X"$mf" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$mf" |
+    sed -n 's,^am--depfiles:.*,X,p' "$am_mf" | grep X >/dev/null 2>&1 \
+      || continue
+    am_dirpart=`$as_dirname -- "$am_mf" ||
+$as_expr X"$am_mf" : 'X\(.*[^/]\)//*[^/][^/]*/*$' \| \
+	 X"$am_mf" : 'X\(//\)[^/]' \| \
+	 X"$am_mf" : 'X\(//\)$' \| \
+	 X"$am_mf" : 'X\(/\)' \| . 2>/dev/null ||
+$as_echo X"$am_mf" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -6825,53 +6898,48 @@ $as_echo X"$mf" |
 	    q
 	  }
 	  s/.*/./; q'`
-    else
-      continue
-    fi
-    # Extract the definition of DEPDIR, am__include, and am__quote
-    # from the Makefile without running 'make'.
-    DEPDIR=`sed -n 's/^DEPDIR = //p' < "$mf"`
-    test -z "$DEPDIR" && continue
-    am__include=`sed -n 's/^am__include = //p' < "$mf"`
-    test -z "$am__include" && continue
-    am__quote=`sed -n 's/^am__quote = //p' < "$mf"`
-    # Find all dependency output files, they are included files with
-    # $(DEPDIR) in their names.  We invoke sed twice because it is the
-    # simplest approach to changing $(DEPDIR) to its actual value in the
-    # expansion.
-    for file in `sed -n "
-      s/^$am__include $am__quote\(.*(DEPDIR).*\)$am__quote"'$/\1/p' <"$mf" | \
-	 sed -e 's/\$(DEPDIR)/'"$DEPDIR"'/g'`; do
-      # Make sure the directory exists.
-      test -f "$dirpart/$file" && continue
-      fdir=`$as_dirname -- "$file" ||
-$as_expr X"$file" : 'X\(.*[^/]\)//*[^/][^/]*/*$' \| \
-	 X"$file" : 'X\(//\)[^/]' \| \
-	 X"$file" : 'X\(//\)$' \| \
-	 X"$file" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$file" |
-    sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
-	    s//\1/
-	    q
-	  }
-	  /^X\(\/\/\)[^/].*/{
+    am_filepart=`$as_basename -- "$am_mf" ||
+$as_expr X/"$am_mf" : '.*/\([^/][^/]*\)/*$' \| \
+	 X"$am_mf" : 'X\(//\)$' \| \
+	 X"$am_mf" : 'X\(/\)' \| . 2>/dev/null ||
+$as_echo X/"$am_mf" |
+    sed '/^.*\/\([^/][^/]*\)\/*$/{
 	    s//\1/
 	    q
 	  }
-	  /^X\(\/\/\)$/{
+	  /^X\/\(\/\/\)$/{
 	    s//\1/
 	    q
 	  }
-	  /^X\(\/\).*/{
+	  /^X\/\(\/\).*/{
 	    s//\1/
 	    q
 	  }
 	  s/.*/./; q'`
-      as_dir=$dirpart/$fdir; as_fn_mkdir_p
-      # echo "creating $dirpart/$file"
-      echo '# dummy' > "$dirpart/$file"
-    done
+    { echo "$as_me:$LINENO: cd "$am_dirpart" \
+      && sed -e '/# am--include-marker/d' "$am_filepart" \
+        | $MAKE -f - am--depfiles" >&5
+   (cd "$am_dirpart" \
+      && sed -e '/# am--include-marker/d' "$am_filepart" \
+        | $MAKE -f - am--depfiles) >&5 2>&5
+   ac_status=$?
+   echo "$as_me:$LINENO: \$? = $ac_status" >&5
+   (exit $ac_status); } || am_rc=$?
   done
+  if test $am_rc -ne 0; then
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+as_fn_error $? "Something went wrong bootstrapping makefile fragments
+    for automatic dependency tracking.  Try re-running configure with the
+    '--disable-dependency-tracking' option to at least be able to build
+    the package (albeit without support for automatic dependency tracking).
+See \`config.log' for more details" "$LINENO" 5; }
+  fi
+  { am_dirpart=; unset am_dirpart;}
+  { am_filepart=; unset am_filepart;}
+  { am_mf=; unset am_mf;}
+  { am_rc=; unset am_rc;}
+  rm -f conftest-deps.mk
 }
  ;;
 
@@ -7655,7 +7723,7 @@ cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 #
 # INIT-COMMANDS
 #
-AMDEP_TRUE="$AMDEP_TRUE" ac_aux_dir="$ac_aux_dir"
+AMDEP_TRUE="$AMDEP_TRUE" MAKE="${MAKE-make}"
 
 _ACEOF
 
@@ -8101,29 +8169,35 @@ $as_echo "$as_me: executing $ac_file commands" >&6;}
   # Older Autoconf quotes --file arguments for eval, but not when files
   # are listed without --file.  Let's play safe and only enable the eval
   # if we detect the quoting.
-  case $CONFIG_FILES in
-  *\'*) eval set x "$CONFIG_FILES" ;;
-  *)   set x $CONFIG_FILES ;;
-  esac
+  # TODO: see whether this extra hack can be removed once we start
+  # requiring Autoconf 2.70 or later.
+  case $CONFIG_FILES in #(
+  *\'*) :
+    eval set x "$CONFIG_FILES" ;; #(
+  *) :
+    set x $CONFIG_FILES ;; #(
+  *) :
+     ;;
+esac
   shift
-  for mf
+  # Used to flag and report bootstrapping failures.
+  am_rc=0
+  for am_mf
   do
     # Strip MF so we end up with the name of the file.
-    mf=`echo "$mf" | sed -e 's/:.*$//'`
-    # Check whether this is an Automake generated Makefile or not.
-    # We used to match only the files named 'Makefile.in', but
-    # some people rename them; so instead we look at the file content.
-    # Grep'ing the first line is not enough: some people post-process
-    # each Makefile.in and add a new line on top of each file to say so.
-    # Grep'ing the whole file is not good either: AIX grep has a line
+    am_mf=`$as_echo "$am_mf" | sed -e 's/:.*$//'`
+    # Check whether this is an Automake generated Makefile which includes
+    # dependency-tracking related rules and includes.
+    # Grep'ing the whole file directly is not great: AIX grep has a line
     # limit of 2048, but all sed's we know have understand at least 4000.
-    if sed -n 's,^#.*generated by automake.*,X,p' "$mf" | grep X >/dev/null 2>&1; then
-      dirpart=`$as_dirname -- "$mf" ||
-$as_expr X"$mf" : 'X\(.*[^/]\)//*[^/][^/]*/*$' \| \
-	 X"$mf" : 'X\(//\)[^/]' \| \
-	 X"$mf" : 'X\(//\)$' \| \
-	 X"$mf" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$mf" |
+    sed -n 's,^am--depfiles:.*,X,p' "$am_mf" | grep X >/dev/null 2>&1 \
+      || continue
+    am_dirpart=`$as_dirname -- "$am_mf" ||
+$as_expr X"$am_mf" : 'X\(.*[^/]\)//*[^/][^/]*/*$' \| \
+	 X"$am_mf" : 'X\(//\)[^/]' \| \
+	 X"$am_mf" : 'X\(//\)$' \| \
+	 X"$am_mf" : 'X\(/\)' \| . 2>/dev/null ||
+$as_echo X"$am_mf" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -8141,53 +8215,48 @@ $as_echo X"$mf" |
 	    q
 	  }
 	  s/.*/./; q'`
-    else
-      continue
-    fi
-    # Extract the definition of DEPDIR, am__include, and am__quote
-    # from the Makefile without running 'make'.
-    DEPDIR=`sed -n 's/^DEPDIR = //p' < "$mf"`
-    test -z "$DEPDIR" && continue
-    am__include=`sed -n 's/^am__include = //p' < "$mf"`
-    test -z "$am__include" && continue
-    am__quote=`sed -n 's/^am__quote = //p' < "$mf"`
-    # Find all dependency output files, they are included files with
-    # $(DEPDIR) in their names.  We invoke sed twice because it is the
-    # simplest approach to changing $(DEPDIR) to its actual value in the
-    # expansion.
-    for file in `sed -n "
-      s/^$am__include $am__quote\(.*(DEPDIR).*\)$am__quote"'$/\1/p' <"$mf" | \
-	 sed -e 's/\$(DEPDIR)/'"$DEPDIR"'/g'`; do
-      # Make sure the directory exists.
-      test -f "$dirpart/$file" && continue
-      fdir=`$as_dirname -- "$file" ||
-$as_expr X"$file" : 'X\(.*[^/]\)//*[^/][^/]*/*$' \| \
-	 X"$file" : 'X\(//\)[^/]' \| \
-	 X"$file" : 'X\(//\)$' \| \
-	 X"$file" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$file" |
-    sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
-	    s//\1/
-	    q
-	  }
-	  /^X\(\/\/\)[^/].*/{
+    am_filepart=`$as_basename -- "$am_mf" ||
+$as_expr X/"$am_mf" : '.*/\([^/][^/]*\)/*$' \| \
+	 X"$am_mf" : 'X\(//\)$' \| \
+	 X"$am_mf" : 'X\(/\)' \| . 2>/dev/null ||
+$as_echo X/"$am_mf" |
+    sed '/^.*\/\([^/][^/]*\)\/*$/{
 	    s//\1/
 	    q
 	  }
-	  /^X\(\/\/\)$/{
+	  /^X\/\(\/\/\)$/{
 	    s//\1/
 	    q
 	  }
-	  /^X\(\/\).*/{
+	  /^X\/\(\/\).*/{
 	    s//\1/
 	    q
 	  }
 	  s/.*/./; q'`
-      as_dir=$dirpart/$fdir; as_fn_mkdir_p
-      # echo "creating $dirpart/$file"
-      echo '# dummy' > "$dirpart/$file"
-    done
+    { echo "$as_me:$LINENO: cd "$am_dirpart" \
+      && sed -e '/# am--include-marker/d' "$am_filepart" \
+        | $MAKE -f - am--depfiles" >&5
+   (cd "$am_dirpart" \
+      && sed -e '/# am--include-marker/d' "$am_filepart" \
+        | $MAKE -f - am--depfiles) >&5 2>&5
+   ac_status=$?
+   echo "$as_me:$LINENO: \$? = $ac_status" >&5
+   (exit $ac_status); } || am_rc=$?
   done
+  if test $am_rc -ne 0; then
+    { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+as_fn_error $? "Something went wrong bootstrapping makefile fragments
+    for automatic dependency tracking.  Try re-running configure with the
+    '--disable-dependency-tracking' option to at least be able to build
+    the package (albeit without support for automatic dependency tracking).
+See \`config.log' for more details" "$LINENO" 5; }
+  fi
+  { am_dirpart=; unset am_dirpart;}
+  { am_filepart=; unset am_filepart;}
+  { am_mf=; unset am_mf;}
+  { am_rc=; unset am_rc;}
+  rm -f conftest-deps.mk
 }
  ;;
 

configure.ac

@@ -8,8 +8,6 @@ AC_LANG(C++)
 AC_CANONICAL_HOST
 AM_INIT_AUTOMAKE
 
-
-
 # Define --wth-* and --enable-* arguments
 
 AC_ARG_WITH(qtsingleapplication,
@@ -204,6 +202,32 @@ PKG_CHECK_MODULES(zlib,
                  [CPPFLAGS="$zlib_CFLAGS $CPPFLAGS"
                  LIBS="$zlib_LIBS $LIBS"])
 
+# Check compiler C++11 support
+AC_LANG_PUSH(C++)
+m4_define([DETECT_CPP11_PROGRAM],
+    [AC_LANG_PROGRAM([[
+#ifndef __cplusplus
+#error "This is not a C++ compiler"
+#elif __cplusplus < 201103L
+#error "This is not a C++11 compiler"
+#endif]],
+    [[]])])
+
+_tmp="$CXXFLAGS"
+CXXFLAGS="$CXXFLAGS -std=c++11"
+AC_COMPILE_IFELSE([DETECT_CPP11_PROGRAM()],
+    [],
+    [AC_MSG_ERROR([A compiler supporting C++11 is required.])])
+
+CXXFLAGS="$_tmp $libtorrent_CFLAGS"
+AC_COMPILE_IFELSE([DETECT_CPP11_PROGRAM()],
+    [],
+    [AC_MSG_ERROR([Compiler is not working in C++11 or later mode.
+    Make sure you use the same C++ mode for qBittorrent and its dependencies.
+    Example: `CXXFLAGS="\$CXXFLAGS -std=c++11" ./configure`])])
+CXXFLAGS="$_tmp"
+AC_LANG_POP([C++])
+
 # These are required because autoconf doesn't expand these **particular**
 # vars automatically. And qmake cannot autoexpand them.
 AX_DEFINE_DIR([EXPAND_PREFIX], [prefix])

src/src.pro

@@ -2,9 +2,6 @@
 TEMPLATE = app
 CONFIG += qt thread silent
 
-# C++11 support
-CONFIG += c++11
-
 # Platform specific configuration
 win32: include(../winconf.pri)
 macx: include(../macxconf.pri)