Question

#include <iostream>
#include <cilk/cilk.h>

int fib(int n)
{
 if (n < 2)
 return n;
 int x = cilk_spawn fib(n-1);
 int y = fib(n-2);
 cilk_sync;
 return x + y;
}

int main(int argc, char ** argv)
{
    for (int i = 0; i != 20; ++i)
    {
        std::cout << "fib(i)=" << fib(i) << std::endl;
    }
}

如此编译，无法找到库

$ g++ -Wall -O3 -fcilkplus fib.cpp -o fib          
/opt/rh/devtoolset-4/root/usr/libexec/gcc/x86_64-redhat-linux/5.2.1/ld: cannot find -lcilkrts
collect2: error: ld returned 1 exit status

所以我尝试使用-L开关

查找并添加它

$ find / opt / rh / devtoolset-4 -name＆＃34; cilkrts ＆＃34; /opt/rh/devtoolset-4/root/usr/lib/gcc/x86_64-redhat-linux/5.2.1/32/libcilkrts.a /opt/rh/devtoolset-4/root/usr/lib/gcc/x86_64-redhat-linux/5.2.1/32/libcilkrts.so /opt/rh/devtoolset-4/root/usr/lib/gcc/x86_64-redhat-linux/5.2.1/libcilkrts.spec

$ g++ -Wall -O3 -fcilkplus fib.cpp -o fib -L/opt/rh/devtoolset-4/root/usr/lib/gcc/x86_64-redhat-linux/5.2.1/32
/opt/rh/devtoolset-4/root/usr/libexec/gcc/x86_64-redhat-linux/5.2.1/ld: skipping incompatible /opt/rh/devtoolset-4/root/usr/lib/gcc/x86_64-redhat-linux/5.2.1/32/libstdc++.so when searching for -lstdc++
/opt/rh/devtoolset-4/root/usr/libexec/gcc/x86_64-redhat-linux/5.2.1/ld: skipping incompatible /opt/rh/devtoolset-4/root/usr/lib/gcc/x86_64-redhat-linux/5.2.1/32/libcilkrts.so when searching for -lcilkrts
/opt/rh/devtoolset-4/root/usr/libexec/gcc/x86_64-redhat-linux/5.2.1/ld: cannot find -lcilkrts
/opt/rh/devtoolset-4/root/usr/libexec/gcc/x86_64-redhat-linux/5.2.1/ld: skipping incompatible /opt/rh/devtoolset-4/root/usr/lib/gcc/x86_64-redhat-linux/5.2.1/32/libgcc_s.so when searching for -lgcc_s
/opt/rh/devtoolset-4/root/usr/libexec/gcc/x86_64-redhat-linux/5.2.1/ld: skipping incompatible /opt/rh/devtoolset-4/root/usr/lib/gcc/x86_64-redhat-linux/5.2.1/32/libgcc.a when searching for libgcc.a
collect2: error: ld returned 1 exit status


$ g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/opt/rh/devtoolset-4/root/usr/libexec/gcc/x86_64-redhat-linux/5.2.1/lto-wrapper
Target: x86_64-redhat-linux
Configured with: ../configure --enable-bootstrap --enable-languages=c,c++,fortran,lto --prefix=/opt/rh/devtoolset-4/root/usr --mandir=/opt/rh/devtoolset-4/root/usr/share/man --infodir=/opt/rh/devtoolset-4/root/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-shared --enable-threads=posix --enable-checking=release --enable-multilib --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-gnu-unique-object --enable-linker-build-id --enable-plugin --with-linker-hash-style=gnu --enable-initfini-array --disable-libgcj --with-default-libstdcxx-abi=gcc4-compatible --with-isl=/builddir/build/BUILD/gcc-5.2.1-20150902/obj-x86_64-redhat-linux/isl-install --enable-libmpx --enable-gnu-indirect-function --with-tune=generic --with-arch_32=i686 --build=x86_64-redhat-linux
Thread model: posix
gcc version 5.2.1 20150902 (Red Hat 5.2.1-2) (GCC)

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Answer 1

如果我问它，我想我应该在解决时发布答案：

sudo yum install devtoolset-4-libcilkrts-devel

是缺失的部分。

编译cilk加代码centos 7 gcc-5.2 devtoolset-4

1 个答案: