这是我的程序：
#include <string>
#include <log4cplus/logger.h>
int main()
{
log4cplus::Logger::getInstance(std::string("main"));
}
建造：
$ g++ main.cpp -llog4cplus
/tmp/ccBqwrxF.o:main.cpp:function main: error: undefined reference to 'log4cplus::Logger::getInstance(std::string const&)'
collect2: error: ld returned 1 exit status
$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=20.04
DISTRIB_CODENAME=focal
DISTRIB_DESCRIPTION="Ubuntu 20.04 LTS"
$ dpkg -l g++ liblog4cplus-dev
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-================-================-============-======================================================================
ii g++ 4:9.3.0-1ubuntu2 amd64 GNU C++ compiler
ii liblog4cplus-dev 1.1.2-3.2build1 amd64 C++ logging API modeled after the Java log4j API - development library
详细：
$ g++ main.cpp -llog4cplus --verbose
Using built-in specs.
COLLECT_GCC=/usr/bin/g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/9/lto-wrapper
OFFLOAD_TARGET_NAMES=nvptx-none:hsa
OFFLOAD_TARGET_DEFAULT=1
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 9.3.0-10ubuntu2' --with-bugurl=file:///usr/share/doc/gcc-9/README.Bugs --enable-languages=c,ada,c++,go,brig,d,fortran,objc,obj-c++,gm2 --prefix=/usr --with-gcc-major-version-only --program-suffix=-9 --program-prefix=x86_64-linux-gnu- --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --libdir=/usr/lib --enable-nls --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --with-default-libstdcxx-abi=new --enable-gnu-unique-object --disable-vtable-verify --enable-plugin --enable-default-pie --with-system-zlib --with-target-system-zlib=auto --enable-objc-gc=auto --enable-multiarch --disable-werror --with-arch-32=i686 --with-abi=m64 --with-multilib-list=m32,m64,mx32 --enable-multilib --with-tune=generic --enable-offload-targets=nvptx-none,hsa --without-cuda-driver --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 9.3.0 (Ubuntu 9.3.0-10ubuntu2)
COLLECT_GCC_OPTIONS='-D' '_GLIBCXX_USE_CXX11_ABI=0' '-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64'
/usr/lib/gcc/x86_64-linux-gnu/9/cc1plus -quiet -v -imultiarch x86_64-linux-gnu -D_GNU_SOURCE -D _GLIBCXX_USE_CXX11_ABI=0 main.cpp -quiet -dumpbase main.cpp -mtune=generic -march=x86-64 -auxbase main -version -fasynchronous-unwind-tables -fstack-protector-strong -Wformat -Wformat-security -fstack-clash-protection -fcf-protection -o /tmp/ccgtz74p.s
GNU C++14 (Ubuntu 9.3.0-10ubuntu2) version 9.3.0 (x86_64-linux-gnu)
compiled by GNU C version 9.3.0, GMP version 6.2.0, MPFR version 4.0.2, MPC version 1.1.0, isl version isl-0.22.1-GMP
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
ignoring duplicate directory "/usr/include/x86_64-linux-gnu/c++/9"
ignoring nonexistent directory "/usr/local/include/x86_64-linux-gnu"
ignoring nonexistent directory "/usr/local/include"
ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/9/include-fixed"
ignoring nonexistent directory "/usr/lib/gcc/x86_64-linux-gnu/9/../../../../x86_64-linux-gnu/include"
#include "..." search starts here:
#include <...> search starts here:
/usr/include/c++/9
/usr/include/x86_64-linux-gnu/c++/9
/usr/include/c++/9/backward
/usr/lib/gcc/x86_64-linux-gnu/9/include
/usr/include/x86_64-linux-gnu
/usr/include
End of search list.
GNU C++14 (Ubuntu 9.3.0-10ubuntu2) version 9.3.0 (x86_64-linux-gnu)
compiled by GNU C version 9.3.0, GMP version 6.2.0, MPFR version 4.0.2, MPC version 1.1.0, isl version isl-0.22.1-GMP
GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: a3d04a02fbd98a786d710618ca593f02
COLLECT_GCC_OPTIONS='-D' '_GLIBCXX_USE_CXX11_ABI=0' '-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64'
as -v --64 -o /tmp/ccvqgN1o.o /tmp/ccgtz74p.s
GNU assembler version 2.34 (x86_64-linux-gnu) using BFD version (GNU Binutils for Ubuntu) 2.34
COMPILER_PATH=/usr/lib/gcc/x86_64-linux-gnu/9/:/usr/lib/gcc/x86_64-linux-gnu/9/:/usr/lib/gcc/x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/9/:/usr/lib/gcc/x86_64-linux-gnu/
LIBRARY_PATH=/usr/lib/gcc/x86_64-linux-gnu/9/:/usr/lib/gcc/x86_64-linux-gnu/9/../../../x86_64-linux-gnu/:/usr/lib/gcc/x86_64-linux-gnu/9/../../../../lib/:/lib/x86_64-linux-gnu/:/lib/../lib/:/usr/lib/x86_64-linux-gnu/:/usr/lib/../lib/:/usr/lib/gcc/x86_64-linux-gnu/9/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-D' '_GLIBCXX_USE_CXX11_ABI=0' '-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64'
/usr/lib/gcc/x86_64-linux-gnu/9/collect2 -plugin /usr/lib/gcc/x86_64-linux-gnu/9/liblto_plugin.so -plugin-opt=/usr/lib/gcc/x86_64-linux-gnu/9/lto-wrapper -plugin-opt=-fresolution=/tmp/ccna3Fgp.res -plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lgcc -plugin-opt=-pass-through=-lc -plugin-opt=-pass-through=-lgcc_s -plugin-opt=-pass-through=-lgcc --build-id --eh-frame-hdr -m elf_x86_64 --hash-style=gnu --as-needed -dynamic-linker /lib64/ld-linux-x86-64.so.2 -pie -z now -z relro /usr/lib/gcc/x86_64-linux-gnu/9/../../../x86_64-linux-gnu/Scrt1.o /usr/lib/gcc/x86_64-linux-gnu/9/../../../x86_64-linux-gnu/crti.o /usr/lib/gcc/x86_64-linux-gnu/9/crtbeginS.o -L/usr/lib/gcc/x86_64-linux-gnu/9 -L/usr/lib/gcc/x86_64-linux-gnu/9/../../../x86_64-linux-gnu -L/usr/lib/gcc/x86_64-linux-gnu/9/../../../../lib -L/lib/x86_64-linux-gnu -L/lib/../lib -L/usr/lib/x86_64-linux-gnu -L/usr/lib/../lib -L/usr/lib/gcc/x86_64-linux-gnu/9/../../.. /tmp/ccvqgN1o.o -llog4cplus -lstdc++ -lm -lgcc_s -lgcc -lc -lgcc_s -lgcc /usr/lib/gcc/x86_64-linux-gnu/9/crtendS.o /usr/lib/gcc/x86_64-linux-gnu/9/../../../x86_64-linux-gnu/crtn.o
/tmp/ccvqgN1o.o:main.cpp:function main: error: undefined reference to 'log4cplus::Logger::getInstance(std::string const&)'
collect2: error: ld returned 1 exit status
答案1
该问题是由-D _GLIBCXX_USE_CXX11_ABI=0构建标志引起的。
考虑取消设置此选项。