My Solaris system has two versions of ld installed
The first belongs to solaris studio:
$ /usr/ccs/bin/ld -V
ld: Software Generation Utilities - Solaris Link Editors: 5.10-1.1514
And the other one to gcc
$ ld -v
GNU ld (GNU Binutils) 2.24
I try to use gcc and ld
$ which gcc
/usr/bin/gcc
/usr/bin/gcc -> /opt/csw/bin/gcc
$ which ld
/usr/bin/ld
/usr/bin/ld -> /opt/csw/gnu/ld
But when asking gcc which program it uses, it is determined to use the Solaris Studio linker:
$ gcc -print-prog-name=ld
/usr/ccs/bin/ld
Question: how can I get gcc to use the linker at /opt/csw/gnu/ld?
gcc is compiled by default to use the Solaris linker. You can override this setting by using the LD_ALTEXEC environment variable:
export LD_ALTEXEC=/opt/csw/gnu/ld
Related
Is there any way to run gcc with the following flags on an apple M1 chip?
gcc -m32 -o test test.c
It outputs the following error:
ld: unknown/unsupported architecture name for: -arch armv4t
clang: error: linker command failed with exit code 1 (use -v to see invocation)
You may not run 32-bit applications on macos Catalina or newer. The oldest version of macOS supported on any Apple Silicon (M1/M2) systems is Big Sur, which is the release after Catalina.
So use of -m32 on gcc or any other compiler on macOS is a not supported. Well, I suppose you could use a cross compiler to target a different operating system than the machine you are running the compiler.
Fix:
Remove -m32 and fix any issues with the code.
you can try using an IDE like Xcode or CLion as a workaround while they update GCC.
I am trying to compile simple C code on my system. I am running gcc version (4.9.2) on macOS 10.11.6.
ld: library not found for -lgcc
collect2: error: ld returned 1 exit status
I am unable to fix this issue. This problem is not letting me install any ./configure packages as well since they require gcc to work.
Even if there is a program called gcc under macOS, it is not a real gcc compiler. It is just a Clang compiler, as you can prove easily:
gcc --version
will print:
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 9.0.0 (clang-900.0.39.2)
Target: x86_64-apple-darwin17.4.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
You should be able to compile and link your program by omitting the -lgcc flag from the command line.
I already have gcc and g++ install:
$ which gcc
/usr/bin/gcc
$ which g++
/usr/bin/g++
$ brew install gcc
Warning: gcc-6.2.0 already installed
I follow Compile OpenMP programs with gcc compiler on OS X Yosemite to reinstall gcc via HomeBrew:
$ brew reinstall gcc --without-multilib
then
$ /usr/bin/g++ openmp.cpp
openmp.cpp:12:10: fatal error: 'omp.h' file not found
#include <omp.h>
^
1 error generated.
with -fopenmp
$ /usr/bin/g++ openmp.cpp -fopenmp
clang: error: unsupported option '-fopenmp'
clang: error: unsupported option '-fopenmp'
What's happening with this redirection? How could I use gcc/g++?
Though involved, it's not about OpenMP.
brew installs tools in /usr/local/bin. Use /usr/local/bin/g++6:
$ /usr/local/bin/g++-6 --version
g++-6 (Homebrew gcc 6.2.0) 6.2.0
Copyright (C) 2016 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
If I have:
$ gcc -v -lm -lc math.o 2> logg
There are no libc or libm in the resulting link logg. Is that normal?
$ gcc --version
gcc (Ubuntu 4.9.1-16ubuntu6) 4.9.1
I am trying to compile opencv 2.4.5 with CUDA support in Mac OS X. I am using the cmake gui 2.8.10 with Qt 4.8
After a
clang: error: unsupported option '-dumpspecs'
in the make i have set the entry CUDA_HOST_COMPILER to /usr/bin/llvm-g++ . But now I receive this error:
[ 16%] Built target IlmImf
[ 16%] Building NVCC (Device) object modules/core/CMakeFiles/cuda_compile.dir/src/cuda/./cuda_compile_generated_matrix_operations.cu.o
cc1plus: warning: command line option "-Wmissing-declarations" is valid for C/ObjC but not for C++
cc1plus: warning: command line option "-Wstrict-prototypes" is valid for Ada/C/ObjC but not for C++
cc1plus: error: unrecognized command line option "-Wno-narrowing"
cc1plus: error: unrecognized command line option "-Wno-delete-non-virtual-dtor"
cc1plus: error: unrecognized command line option "-Wno-unnamed-type-template-args"
What can i do now?
SYSTEM SETTINGS
OS X 10.8.3 (12D78)
and
>>> clang --version
Apple LLVM version 4.2 (clang-425.0.24) (based on LLVM 3.2svn)
Target: x86_64-apple-darwin12.3.0
Thread model: posix
and
>>> g++ --version
i686-apple-darwin11-llvm-g++-4.2 (GCC) 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.11.00)
>>> ls -al /usr/bin/g++
/usr/bin/g++ -> llvm-g++-4.2
and
>>> cc --version
Apple LLVM version 4.2 (clang-425.0.24) (based on LLVM 3.2svn)
Target: x86_64-apple-darwin12.3.0
Thread model: posix
>>> ls -al /usr/bin/cc
/usr/bin/cc -> clang
Use GCC and G++ to compile. I've used CMake 2.8.11 on OSX Mountain Lion with latest Xcode compilers:
g++ --version returns i686-apple-darwin11-llvm-g++-4.2 (GCC) 4.2.1 (Based on Apple Inc. build 5658) (LLVM build 2336.11.00)
Change the CUDA_HOST_COMPILER from /usr/bin/cc to /usr/bin/gcc
You have to compile the CUDA components using GCC 4.5, while compiling the rest of OpenCV with Clang, otherwise you cannot get the HighGui module to work. HighGui will only compile with the Apple installed compilers because it uses Cocoa. If you do not need HighGui, you can compile OpenCV with GCC. You can specify the proper compilers quite easily with cmake.
I found that the easiest way was to use Homebrew to install cmake and gcc.
I wrote up a detailed gist of how to make it work here that also includes enabling Python support using the Homebrew version.
Disable warning flags in cmake/OpenCVCompilerOptions. Find corresponding warnings and uncomment them using '#'