I'm trying to use the asmlibrary which I've obtained from here
I'm running in 64-bit, but the pre-compiled static library is build for 32-bit.
I don't really want to recompile the library, because I do not have OpenCV 1.0 installed, and don't really want to install such an old version of this piece of software.
My employer has told me that you may use ia32-libs which would allow me to use the library on a 64-bit machine. I have installed these libs using apt.
In netbeans, my IDE of choice, I'm now attempting to use the library. I keep getting the messages:
/usr/bin/ld: i386 architecture of input file
`../asmlib/libasmlibrary.a(asm_shape.o)' is incompatible with
i386:x86-64 output
Etc..
I have two questions:
1) Will ia32-libs allow me to use this library?
2) How must I "enable" it's use, either generally or preferably specific to netbeans (if applicable)
Thank you
An executable (including the libraries it depends on) has to be entirely 32 bits or 64 bits. You cannot mix and match object files of different types.
So to use a 32 bits library, you must compile your program as a 32 bits executable and link with a 32 bits version of libc and other core libraries. On debian you'll need packages like libc6-dev-i386 and ia32-libs-dev.
To compile foo.c as a 32 bits executable, use
gcc -m32 -o foo foo.c
How to do this with netbeans is left as an exercise.
I don't think that you are able to use ia32-libs to compile a 64-bit program, using 32-bit libraries. That isn't what ia32-libs is designed for...it's designed to run entirely 32-bit programs on 64-bit systems.
I think your best bet would be to compile as 32-bit software. If you were using the command line, you can just add the -m32 flag to gcc. With netbeans, in Project Properties > Build > C Compiler (or C++ compiler if that's what you are using), there is a dropdown to select architecture. If 32-bit is not available in that dropdown, you can add -m32 to the Additional Options box.
Related
I have a Fortran program(.f) that I have written in Ubuntu Linux. I compiled the written Fortran program in Linux by using the below command and it it successfully executed.
gfortran -o program program.f
Now I want to execute the same Fortran program in Windows 10 Can it be executed in window system? If so please suggest me a way to do it.
I tried gfortran -o program program.f in Windows command window,but it fails.
To compile Fortran code for Windows you need a Fortran compiler for Windows. Microsoft neither provides a built-in one nor offers one for sale. Third-party compilers are available, including gfortran, but you'll need to install one yourself. If you want to use gfortran in particular, or if you like it simply because you don't have to spend money to get it, then I would recommend obtaining it as part of mingw-w64. Alternatives are available from multiple vendors, some free of charge, but most for sale.
Note also that Windows expects executables to be named with an .exe extenstion, so you would want to use a variation on gfortran your compilation command:
gfortran -o program.exe program.f
If you want to use gfortran on Windows, I suggest you install MSYS2, which has a bash terminal, and a package manager that can install gcc and gfortran, as well as lapack and many other libraries.
There is also a separate distribution of mingw-w64 that can be installed without MSYS2, but I don't recommend it, as the last files there have gcc-8.1.0, from 2018 (apart from a recent build by Ray Linn that includes the Ada, but not the Fortran compiler).
Another compiler that is now free is Intel Fortran : you have to install Microsoft Visual Studio Community, Intel oneAPI Base Toolkit and Intel oneAPI HPC Toolkit. More information here. Available on Linux, macOS and Windows (of course, Visual Studio is needed only on Windows). Intel oneAPI is at least partly open source, not sure about the Fortran compiler.
MSYS2 is a much smaller package (in terms of disk pace needed), and is used by several other free projects: R (Rtools), Octave and Strawberry Perl all include parts of it, including the gcc compilers.
On my 64-bit RHEL machine, I'm compiling and running a C & Fortran program that is 32-bit only. It invokes the non-static version of a lot of standard Linux libs (X11, OpenGL/Mesa, Motif, etc...), which of course invoke other libs (libjpeg, libc, etc). Do I have to install the 32-bit versions of that entire devl lib tree in order to build this program validly? And do I have to install the 32-bit versions of that entire run-time lib tree in order to run it without it segfaulting or whatever?
As far as i know you can't use 64 bit versions of your libs to run 32 bit software. So yes you need the 32 bit versions.
I am using Ubuntu 13.04 and installed mingw-w64 using apt-get install mingw-w64. I can compile and link a working 64-bit version of my program with the following command:
x86_64-w64-mingw32-g++ code.cpp -o app.exe
Which generates a 64-bit app.exe file.
What binary or command line flags do I use to generate a 32-bit version of app.exe?
That depends on which variant of toolchain you're currently using. Both DWARF and SEH variants (which come starting from GCC 4.8.0) are only single-target. You can see it yourself by inspecting the directory structure of their distributions, i.e. they contain only the libraries with either 64- or 32-bit addressing, but not both. On the other hand, plain old SJLJ distributions are indeed dual-target, and in order to build 32-bit target, just supply -m32 flag. If that doesn't work, then just build with i686-w64-mingw32-g++.
BONUS
By the way, the three corresponding dynamic-link libraries (DLLs) implementing each GCC exception model are
libgcc_s_dw2-1.dll (DWARF);
libgcc_s_seh-1.dll (SEH);
libgcc_s_sjlj-1.dll (SJLJ).
Hence, to find out what exception model does your current MinGW-w64 distribution exactly provide, you can either
inspect directory and file structure of MinGW-w64 installation in hope to locate one of those DLLs (typically in bin); or
build some real or test C++ code involving exception handling to force linkage with one of those DLLs and then see on which one of those DLLs does the built target depend (for example, can be seen with Dependency Walker on Windows); or
take brute force approach and compile some test code to assembly (instead of machine code) and look for presence of references like ___gxx_personality_v* (DWARF), ___gxx_personality_seh* (SEH), ___gxx_personality_sj* (SJLJ); see Obtaining current GCC exception model.
I have found the code which links against of 'g2c' library. Why do I need it? Just would like to understand why it might be important and what it does in general.
Thanks!
What is GNU Fortran?
g77 consists of several components:
A modified version of the gcc command, which also might be installed as the system's cc command. (In many cases, cc refers to the system's “native” C compiler, which might be a non-GNU compiler, or an older version of gcc considered more stable or that is used to build the operating system kernel.)
The g77 command itself, which also might be installed as the system's f77 command.
The libg2c run-time library. This library contains the machine code needed to support capabilities of the Fortran language that are not directly provided by the machine code generated by the g77 compilation phase.
libg2c is just the unique name g77 gives to its version of libf2c to distinguish it from any copy of libf2c installed from f2c (or versions of g77 that built libf2c under that same name) on the system.
You may think of it as, libg2c is to g77 as libc is to gcc.
Note that as of the GCC 4.x series, g77 has been discontinued, replaced by gfortran, which produces programs that do not require an extra libg2c runtime library.
"This library contains the machine code needed to support capabilities of the Fortran language that are not directly provided by the machine code generated by the g77 compilation phase."
from this link
Installing compat-gcc-34-g77 solves this requirement.
(gcc-34 must be replaced by your gcc version)
What is the best way to compile programs with DMD on a 64bit machine? It doesn't need to compile to 64Bit code. I know about GDC, but want to work with D2 also. There is also chroot, but am hoping for a simpler way.
The actual problem isn't with compiling, but linking. DMD calls on GCC to perform linking with system libraries. Could I get DMD to have GCC link against 32bit library? Or how would I do it manually?
I already have the ia32 libraries installed which is why I can run DMD.
Ask GCC to perform 32-bit link by passing it '-m32' flag.
It appears that DMD doesn't invoke gcc to perform the link, but rather invokes ld directly. The equivalent ld switch is '-melf_i386', and apparently the way to make DMD pass that option to the linker is with '-L-melf_i386' flag.
Note that many systems separate runtime and development libraries. 32-bit runtime packages are almost always installed by default, but 32-bit development packages may not be.
You need development 32-bit packages to build 32-bit programs. The fact that 32-bit DMD can run does not in itself prove that you have all the 32-bit libraries you need in order to build 32-bit programs.