Yestoday, I tried to upgrade my gcc from version 8.4.0 to 9.3.0 by building from source, because the latest version that can be installed through apt repo of Ubuntu, is 8.4.0.
Building and installing proccesses are all OK, and I can compile whatever c++ code even though including the features those are implemented only by gcc-9.3.0. But I can NOT run my programs, if I used c++ STL in my code.
By means of "ldd my-program", I found the problem.
It looks like that gcc-9.3.0 installed the file libstdc++.so.6.0.28 into /usr/lib64/, while the one(libstdc++.so.6.0.25) of the official version(gcc-8.4.0) resides in /usr/lib/x86_64-linux-gnu/, so ld.so can NOT load libs for my-program.
If I add "/usr/lib64" into LD_LIBRARY_PATH env var, it works.
It's strange that /usr/lib64 is NOT the one of the default searching locations of ld.so of Kubuntu-18.04.4LTS, or I am wrong?
I know it can be resolved by using LD_LIBRARY_PATH or add path into /etc/ld.so.conf, I'm just wondering /usr/lib64 is NOT the default path.
Additionally, I reviewed the building proccess:
In order to make the targets as close as possible to the official targets those come from Ubuntu's apt repo,
before configuring, I used "echo | gcc -v -x c -E -" to get all the build options of the official gcc-8.4.0 targets,
and then apply them to myself buiding as following:
~/projects/gcc-9.3.0/configure \
--build=x86_64-linux-gnu \
--disable-libgcj \
--disable-libstdcxx-debug \
--disable-libunwind-exceptions \
--disable-multilib \
--disable-vtable-verify \
--enable-__cxa_atexit \
--enable-bootstrap \
--enable-checking=release \
--enable-clocale=gnu \
--enable-default-pie \
--enable-gnu-indirect-function \
--enable-gnu-unique-object \
--enable-initfini-array \
--enable-languages=c,c++ \
--enable-libmpx \
--enable-libstdcxx-time=yes \
--enable-linker-build-id \
--enable-nls \
--enable-offload-targets=nvptx-none \
--enable-plugin \
--enable-shared \
--enable-threads=posix \
--host=x86_64-linux-gnu \
--libdir=/usr/lib \
--libexecdir=/usr/lib \
--prefix=/usr \
--program-suffix=-9.3 \
--target=x86_64-linux-gnu \
--with-abi=m64 \
--with-bugurl=file:///usr/share/doc/gcc-8/README.Bugs \
--with-default-libstdcxx-abi=new \
--with-linker-hash-style=gnu \
--with-pkgversion='Ubuntu 9.3.0-6ubuntu1~18.04.4' \
--with-system-zlib \
--with-target-system-zlib \
--with-tune=generic \
--without-cuda-driver \
--without-included-gettext
Pls note the option "--libdir=/usr/lib" explicitly sets the path to which the target-libs should be installed. But the file libstdc++.so.6.0.28 was still installed to /usr/lib64 finally.
What things did I missed?
Any help or hint will be appretiated!
