my custom built gcc 4.6.0, installed in my home directory, on ubuntu 10.04, links the system libstdc++ instead of the custom built one, most of the time (as evidenced by ldd). to be more puzzling, using this newly built gcc, custom compiled openmpi libraries are linked correctly, and this is the only software i have compiled that behaves ok. does anybody have any explanation for this, or a workaround?
thanks
Isn't there an option to statically link the libstdc into the gcc when you configure it? --disable-shared if I understand how it works correctly. Worst case make another compile of gcc with that switch and see if you run into the issue.
I don't know why this isn't detailed more clearly on the GCC website for end-users. The GCC FAQ clearly states this is a common problem wrt libstdc++. Environment variables are troublesome. Wrapping the linker, nobody knows how to do that. Editing /etc/ld.so.conf isn't an option. Adding -Wl,-rpath everywhere, come on. The easiest solution is the specs file. For a typical 64-bit x86 Linux system, go into your custom gcc installation, in dirname `g++ -print-libgcc-file-name`and then run g++ -dumpspecs > specs. Edit that file, find the *link_command: section. After %(link_libgcc) add -rpath /home/user/bin/gcc-9/lib64 (of course use your own path). Or add the same rpath to end of *link: section. Alternatively, configure gcc with --with-specs='%{!static:%x{-rpath=/home/user/bin/gcc9/lib64} %x{-enable-new-dtags}}' . Enjoy your own C++ compiler that generates binaries that just work.
See also:
GCC specs file: how to get the installation path
Linking g++ 4.8 to libstdc++
How to configure libstdc++ with GCC 4.8?
Related
I want to force new GCC 12 on my old debian (that only has GCC 6 by default) to use fresh libstdc++ headers with new header-only features, but link with old stdlibc++,gcc_s (and other system/compiler libs used by GCC6) to keep binary compatibility with native runtime of old debian (so that users of old GCC6 can link with my binaries without having GCC12).
Of course I know that some functionality in the old runtime will be missing, and ABI is also different, but I guess I can fight with that. Afterall RedHat seems to be using similar scheme for their devtoolset packages (they try to link missing functionality of new runtime statically to your binary if these symbols are not found in native old runtime)
So far I am stuck with -L arguments that GCC is passing to ld.
Here is complete output of /usr/local/gcc12/bin/x86_64-linux-gnu-gcc-12 main.cpp -Wl,-v -v command for simple hello-world main.cpp:
https://pastebin.com/JhYSfg4x
The question: Where does GCC take all these -L paths from, and how do I remove/modify them? I don't want to accidentally link with new version of libraries that were built with GCC12:
-L/usr/lib/gcc/x86_64-linux-gnu -L/usr/local/gcc12/lib/gcc/x86_64-linux-gnu/12 -L/usr/local/gcc12/lib/gcc/x86_64-linux-gnu/12/../../../../lib64 -L/lib/x86_64-linux-gnu -L/lib/../lib64 -L/usr/lib/x86_64-linux-gnu -L/usr/lib/gcc -L/usr/local/gcc12/lib/gcc/x86_64-linux-gnu/12/../../.. /tmp/ccXfhCs4.o
System ld.conf does not mention any paths to /usr/local/gcc12 folder.
-nostdlib and -nodefaultlibs are removing some standard -l flags, but they are not doing anything to -L flags.
Update: I ended up just removing all *.a, .so, *.la files from include, lib and lib64 folders of gcc12, and I also added -L path to native libraries. This way I am sure gcc12 can't pickup one of its libraries for li nking. Not sure if this is good solution, but it works.
My developing/producing environments are all CentOS-7.7.
In order to compile my program with gcc-8.3.0, I have installed "devtoolset-8" on my developing env, but it can not be used in the way same as gcc-4.8.5 that was shipped with CentOS7 oringinally.
Every time I need to compile a program, I must use "scl enable devtoolset-8 -- bash" to switch to gcc8 instead of gcc4.8.5.
When the program was deploying onto the producing-env, there is no gcc8, nor libstdc++.so.6.0.25, so it can not run.
I guess libstdc++.so.6.0.25 should be released with gcc8? I can neither install "devtoolset-8" on the producing-env, nor build gcc8 from source on the producing env.
The version of libstdc++ that can be installed from the official yum repo of CentOS, is libstdc++.so.6.0.19, hence my programs can not be loaded at the producing-env.
How to let such programs to run?
Thanks!
Pls forgive my Ugly English.
In order to not have to copy or ship a separate libstdc++.so but rather link statically (as suggested in a comment) against the C++ runtime, one can link C++ programs with -static-libstdc++ (also specifying -static-libgcc will also make sure that the program does not depend on a recent enough version of libgcc_s.so on the system - although that should rarely be a problem).
There can also be the issue of the target system having a version of glibc that is too old (relative to the build system). In that case, one could anyhow compile gcc of no matter how recent of a version on the older system, so that the resulting C++ executables as well as libstdc++ are linked against the older glibc. Linking C++ programs with -static-libstdc++ will again help to not depend on the program having to be able to find libstdc++.so at run-time.
Finally, the C++ program could also be linked with -static not depending on any dynamic libraries at all.
I have a code running on a PowerPC e500v2 embedded Linux and I want to measure its performance since it is running in an infinite loop. I tried gcc's gprof which was simply by adding -pg option to gcc. When I run the binary on the target device I get this:
./main: /lib/libc.so.6: version GLIBC_2.16 not found (required by ./main)
I am using ELDK 5.6 toolchain with the default CFLAGS and LDFLAGS and these flags: -Wall -lrt -pthread -D_GNU_SOURCE nothing else. Some article suggested defining FORTIFY_SOURCE along with an optimization level but it did not work. I searched for some gcc's feature test macros and tried defining some GLIBC 2.16 specific macros but it did not work.
I faced similar issue with GLIBC 2.17 when I used some structures and functions from <sched.h>, adding _GNU_SOURCE resolved it. Any idea on how to resolve it?
When I run the binary on the target device I get this
Your tool chain targets a version of GLIBC that is newer than what is installed on the target.
This doesn't bite you in non-pg compiles only by accident. An "innocent" change to your source can cause the same problem.
You need to upgrade your target to the version of GLIBC which your toolchain actually builds for.
I'm trying to compile CMake using a non-default GCC installed in /usr/local/gcc530, on Solaris 2.11.
I have LD_LIBRARY_PATH=/usr/local/gcc530/lib/sparcv9
Bootstrap proceeds fine, bootstrapped cmake successfully compiles various object files, but when it tries to link the real cmake (and other executables), I get pages of "undefined reference" errors to various standard library functions, because, as running the link command manually with -Wl,-verbose shows, the linker links with /usr/lib/64/libstdc++.so of the system default, much older GCC.
This is because apparently CMake tries to find curses/ncurses libraries (even if I tell it BUILD_CursesDialog:BOOL=OFF), finds them in /usr/lib/64, and adds -L/usr/lib/64 to build/Source/CMakeFiles/cmake.dir/link.txt, which causes the linker to use libstdc++.so from there, and not my actual GCC's own.
I found a workaround: I can get the path to proper libraries from $CC -m64 -print-file-name=libstdc++.so then put it with -L into LDFLAGS when running ./configure, and all works well then.
Is there a less hacky way? It's really weird that I can't tell GCC to prioritize its own libraries.
Also, is there some way to have CMake explain where different parts of a resulting command line came from?
I have been trying to produce a statically linked "single binary" version of my game for windows. I want to link with sdl, sdl_image and sdl_mixer which in turn pull in a few support libraries. Unfortunately I haven't found a way to get them all to compile and link using cygwin/mingw/gcc. As far as I can tell all existing public versions are only shared libraries / dlls.
Please note that I'm not talking about licencing here. The source will be open thus the GPL/LGPLness of sdl is not relevant.
When compiling your project, you need to make just a couple changes to your makefile.
Instead of sdl-config --libs, use sdl-config --static-libs
Surround the use of the above-mentioned sdl-config --static-libs with -Wl,-Bstatic and -Wl,-Bdynamic. This tells GCC to force static linking, but only for the libraries specified between them.
If your makefile currently looks like:
SDLLIBS=`sdl-config --libs`
Change it to:
SDLLIBS=-Wl,-Bstatic `sdl-config --static-libs` -Wl,-Bdynamic
These are actually the same things you should do on Unix-like systems, but it usually doesn't cause as many errors on Unix-likes if you use the simpler -static flag to GCC, like it does on Windows.
Via this SDL mailing list post it seems that the sdl development tools ship with a sdl-config script that you can use with the --static-libs flag to determine what linker flags you need to use.
Environment: VMWare Virtual Machine with Windows 7 x64 and Equipment we Dev c + + build 7.4.2.569, complilador g+ + (tdm-1) 4.6.1
Once, SDL2-2.0.3 API installed as configuration Dev c ++ is not very clear what I've done as tradition requires command line.
The first problem is that Windows 7 appears to have changed the methodology and they go to his ball. Inventory. Ref. https://stackoverflow.com/users/464581/cheers-and-hth-alf
After the first hurdle, SDL_platform.h is that bad, it's down another, I do not remember where I downloaded, but the next does not work in the indicated version.
We must put SDL2.h ls in the directory of the executable.
D:\prg_desa\zsdl2>g++ bar.cpp main.cpp -o pepe1 -ID:\SDL2-2.0.3\i686-w64-mingw32\include\SDL2 -LD:\SDL2-2.0.3\i686-w64-mingw32\lib -lmingw32 -lSDL2main -lSDL2 -mwindow
I've finally compiled and works SDL2 testing.
That's because the SDL libs are under the LGPL-license.
If you want to static link the libs (you can do that if your recompile them. It needs some hacking into the makefiles though) you have to place your game under some compatible open source license as well.
The SDL-libs come as shared libraries because most programs that use them are closed source. The binary distribution comes in a form that most people need.
On my system (Ubuntu) I have to use the following flags:
-Wl,Bstatic -lSDL_image `sdl-config --libs` -lpng12 -lz -ltiff -ljpeg -lasound -laudio -lesd -Wl,-Bdynamic `directfb-config --libs` -lpulse-simple -lcaca -laa -ldl
That links SDL, SDL_image, and many of their dependencies as static. libdl you never want static, so making a fully-static binary that uses SDL_image is a poor idea. pulse,caca,aa, and directfb can probably be made static. I haven't got far enough to figure them out yet.