openwrt building：为什么工具链把CXX = no

Question

当构建openwrt包avahi时：它显示：

    configure.ac:298: the top level
    autoreconf: Leaving directory `.'
    (cd /home/r3d/Desktop/QSDK/qsdk/build_dir/target-arm_v7-a_uClibc-1.0.14_eabi/avahi/dbus/avahi-0.6.31/./; if [ -x ./configure ]; 
then /usr/bin/find /home/r3d/Desktop/QSDK/qsdk/build_dir/target-arm_v7-a_uClibc-1.0.14_eabi/avahi/dbus/avahi-0.6.31/ 
-name config.guess | xargs -r chmod u+w; /usr/bin/find /home/r3d/Desktop/QSDK/qsdk/build_dir/target-arm_v7-a_uClibc-1.0.14_eabi/avahi/dbus/avahi-0.6.31/ 
-name config.guess | xargs -r -n1 cp 
--remove-destination /home/r3d/Desktop/QSDK/qsdk/scripts/config.guess; /usr/bin/find /home/r3d/Desktop/QSDK/qsdk/build_dir/target-arm_v7-a_uClibc-1.0.14_eabi/avahi/dbus/avahi-0.6.31/ 
-name config.sub | xargs -r chmod u+w; /usr/bin/find /home/r3d/Desktop/QSDK/qsdk/build_dir/target-arm_v7-a_uClibc-1.0.14_eabi/avahi/dbus/avahi-0.6.31/ 
-name config.sub | xargs -r -n1 cp --remove-destination /home/r3d/Desktop/QSDK/qsdk/scripts/config.sub; 
AR=arm-openwrt-linux-uclibcgnueabi-ar 
AS="arm-openwrt-linux-uclibcgnueabi-gcc -c -Os -pipe -march=armv7-a -mfpu=vfpv3-d16 -mfloat-abi=softfp -fhonour-copts -Wno-error=unused-but-set-variable -msoft-float -fpic -DGETTEXT_PACKAGE" 
LD=arm-openwrt-linux-uclibcgnueabi-ld NM=arm-openwrt-linux-uclibcgnueabi-nm 
CC="arm-openwrt-linux-uclibcgnueabi-gcc" 
GCC="arm-openwrt-linux-uclibcgnueabi-gcc" 
CXX="no" 
RANLIB=arm-openwrt-linux-uclibcgnueabi-ranlib STRIP=arm-openwrt-linux-uclibcgnueabi-strip 
OBJCOPY=arm-openwrt-linux-uclibcgnueabi-objcopy OBJDUMP=arm-openwrt-linux-uclibcgnueabi-objdump SIZE=arm-openwrt-linux-uclibcgnueabi-size CFLAGS="-Os -pipe -march=armv7-a -mfpu=vfpv3-d16 -mfloat-abi=softfp -fhonour-copts -Wno-error=unused-but-set-variable -msoft-float -fpic -DGETTEXT_PACKAGE " CXXFLAGS="-Os -pipe -march=armv7-a -mfpu=vfpv3-d16 -mfloat-abi=softfp -fhonour-copts -Wno-error=unused-but-set-variable -msoft-float -fpic -DGETTEXT_PACKAGE " CPPFLAGS="-I/home/r3d/Desktop/QSDK/qsdk/staging_dir/target-arm_v7-a_uClibc-1.0.14_eabi/usr/include -I/home/r3d/Desktop/QSDK/qsdk/staging_dir/target-arm_v7-a_uClibc-1.0.14_eabi/include -I/home/r3d/Desktop/QSDK/qsdk/staging_dir/toolchain-arm_v7-a_gcc-4.8-linaro_uClibc-1.0.14_eabi/usr/include -I/home/r3d/Desktop/QSDK/qsdk/staging_dir/toolchain-arm_v7-a_gcc-4.8-linaro_uClibc-1.0.14_eabi/include " 
LDFLAGS="-L/home/r3d/Desktop/QSDK/qsdk/staging_dir/target-arm_v7-a_uClibc-1.0.14_eabi/usr/lib -L/home/r3d/Desktop/QSDK/qsdk/staging_dir/target-arm_v7-a_uClibc-1.0.14_eabi/lib -L/home/r3d/Desktop/QSDK/qsdk/staging_dir/toolchain-arm_v7-a_gcc-4.8-linaro_uClibc-1.0.14_eabi/usr/lib -L/home/r3d/Desktop/QSDK/qsdk/staging_dir/toolchain-arm_v7-a_gcc-4.8-linaro_uClibc-1.0.14_eabi/lib "  CFLAGS="$CFLAGS -DNDEBUG -DDISABLE_SYSTEMD" ac_cv_header_sys_capability_h=no   ./configure --target=arm-openwrt-linux --host=arm-openwrt-linux --build=x86_64-linux-gnu --program-prefix="" --program-suffix="" --prefix=/usr --exec-prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin --libexecdir=/usr/lib --sysconfdir=/etc --datadir=/usr/share --localstatedir=/var --mandir=/usr/man --infodir=/usr/info --disable-nls   --enable-shared --enable-static --disable-glib --disable-gobject --disable-qt3 --disable-qt4 --disable-gtk --disable-gtk3 --with-xml=expat --disable-dbm --enable-gdbm --enable-libdaemon --disable-python --disable-pygtk --disable-python-dbus --disable-mono --disable-monodoc --disable-doxygen-doc --disable-doxygen-dot --disable-doxygen-man --disable-doxygen-rtf --disable-doxygen-xml --disable-doxygen-chm --disable-doxygen-chi --disable-doxygen-html --disable-doxygen-ps --disable-doxygen-pdf --disable-xmltoman --with-distro=none --with-avahi-user=nobody --with-avahi-group=nogroup --with-autoipd-user=nobody --with-autoipd-group=nogroup --disable-stack-protector --enable-dbus ; fi; )

...

checking whether to build shared libraries... yes
checking whether to build static libraries... yes
checking whether the C++ compiler works... no
configure: error: in `/home/r3d/Desktop/QSDK/qsdk/build_dir/target-arm_v7-a_uClibc-1.0.14_eabi/avahi/dbus/avahi-0.6.31':
configure: error: The C++ compiler does not work
See `config.log' for more details

有arg：CXX =没有

我该怎么办呢？

我在configure.ac上添加ARGS但不起作用。

Answer 1

在rule.mk：

TARGET_CXX:=$(if $(CONFIG_INSTALL_LIBSTDCPP),$(TARGET_CROSS)g++,no)

改成 ：

TARGET_CXX=$(TARGET_CROSS)g++

构建工具链时出错了