I’m building a simple C++ program and I want to temporarily substitute a system supplied shared library with a more recent version of it, for development and testing. I tried setting the LD_LIBRARY_PATH variable but the linker (ld) failed with: /usr/bin/ld: cannot find -lyaml-cpp I expected that to work because according to the ld man … Read more
I’m compiling my C++ app using GCC 4.3. Instead of manually selecting the optimization flags I’m using -march=native, which in theory should add all optimization flags applicable to the hardware I’m compiling on. But how can I check which flags is it actually using? 5 Answers 5
I know I can generate debug symbol using -g option. However the symbol is embeded in the target file. Could gcc generate debug symbol outside the result executable/library? Like .pdb file of windows VC++ compiler did. 5 Answers 5
I’m working on a project that will read compiler error messages of a particular variety and do useful things with them. The sample codebase I’m testing this on (a random open-source application), and hence rebuilding frequently, contains a few bits that generate warnings, which are of no interest to me. How do I disable all … Read more
When I’m compiling openvswitch-1.5.0, I’ve encountered the following compile error: gcc -Wstrict-prototypes -Wall -Wno-sign-compare -Wpointer-arith -Wdeclaration-after-statement -Wformat-security -Wswitch-enum -Wunused-parameter -Wstrict-aliasing -Wbad-function-cast -Wcast-align -Wstrict-prototypes -Wold-style-definition -Wmissing-prototypes -Wmissing-field-initializers -Wno-override-init -g -O2 -export-dynamic ***-lpthread*** -o utilities/ovs-dpctl utilities/ovs-dpctl.o lib/libopenvswitch.a /home/jyyoo/src/dpdk/build/lib/librte_eal.a /home/jyyoo/src/dpdk/build/lib/libethdev.a /home/jyyoo/src/dpdk/build/lib/librte_cmdline.a /home/jyyoo/src/dpdk/build/lib/librte_hash.a /home/jyyoo/src/dpdk/build/lib/librte_lpm.a /home/jyyoo/src/dpdk/build/lib/librte_mbuf.a /home/jyyoo/src/dpdk/build/lib/librte_ring.a /home/jyyoo/src/dpdk/build/lib/librte_mempool.a /home/jyyoo/src/dpdk/build/lib/librte_malloc.a -lrt -lm /usr/bin/ld: /home/jyyoo/src/dpdk/build/lib/librte_eal.a(eal.o): undefined reference to symbol ‘pthread_create@@GLIBC_2.2.5’ /lib/x86_64-linux-gnu/libpthread.so.0: error … Read more
Is there a way for gcc/g++ to dump its preprocessor defines from the command line? I mean things like __GNUC__, __STDC__, and so on. 6 Answers 6
For convenience I added the relevant manpages below. My (mis)understanding first: If I need to separate options with ,, that means that the second -Wl is not another option because it comes before , which means it is an argument to the -rpath option. I don’t understand how -rpath can have a -Wl,. argument! What … Read more
I’m trying to debug a compilation problem, but I cannot seem to get GCC (or maybe it is make??) to show me the actual compiler and linker commands it is executing. Here is the output I am seeing: CCLD libvirt_parthelper libvirt_parthelper-parthelper.o: In function `main’: /root/qemu-build/libvirt-0.9.0/src/storage/parthelper.c:102: undefined reference to `ped_device_get’ /root/qemu-build/libvirt-0.9.0/src/storage/parthelper.c:116: undefined reference to `ped_disk_new’ /root/qemu-build/libvirt-0.9.0/src/storage/parthelper.c:122: … Read more
I’m trying to use GCC (linux) with a makefile to compile my project. I get the following error which is can’t seem to decipher in this context: “No rule to make target ‘vertex.cpp’, needed by ‘vertex.o’. Stop.” This is the makefile: a.out: vertex.o edge.o elist.o main.o vlist.o enode.o vnode.o g++ vertex.o edge.o elist.o main.o vlist.o … Read more
I keep hearing about LLVM all the time. It’s in Perl, then it’s in Haskell, then someone uses it in some other language? What is it? What exactly distinguishes it from GCC (perspectives = safety etc.)? 7 s 7 LLVM is a library that is used to construct, optimize and produce intermediate and/or binary machine … Read more
