I'm trying to compile a C program that has some inline assembly code in Intel format. I'm using GCC 4.9 (installed via Homebrew) on Mac 10.9, and the compiler flags:
gcc-4.9 -m32 -masm=intel -std=gnu99 get_rating.c
Unfortunately I get an error:
error: -masm=intel not supported in this configuration
I've tried many different combinations of the flags, but I keep getting that error. I can't leave out the -masm=intel flag, because the code I'm trying to compile uses Intel.
How can I compile the program? Is it at all possible on my Mac (version 10.9) or do I need to run a virtual machine?
The GCC docs state that Darwin does not support intel, so it seems you are out of luck with the direct approach. Virtual machine as you suggested, cross compiling, converting the assembler to att, and replacing the assembler with C are among your options - which is best for you you'll have to figure out.
HTH
Related
I'm using the Windows version of Clang (LLVM) 8 under Windows.
I'm compiling a code which uses OpenMP.
Under the lib folder of Clang there are 2 files which are OpenMP related:
libomp.lib.
libiomp5md.dll.
My questions are:
When I compile the code I use the flags -Xclang -fopenmp for the compiler. In in GCC and ICC using the flags tell the compiler to link the OpenMP library automatically. What about Clang? Does it do it automatically or must I link with libomp.lib manually? Is there a way to trigger automatic linking to the OpenMP library?
Answer: This was answered in Michael Klemm's answer below - Use the clang driver both for compiling and linking and then the -fopenmp will work as in GCC.
When I link with libomp.lib manually (Defining as a library for the linker) the output exe requires libomp.dll while the supplied OpenMP Dynamic Library is libiomp5md.dll. Is that a bug or is it because I link manually?
Answer: The libomp.dll is supplied in the bin folder and not the lib folder.
What's the proper way to utilize OpenMP in Clang under Windows? The clang-cl driver doesn't work with /openmp or -openmp as the MSVC's cl compiler.
Answer: Currently it can be done either with clang -fopenmp ..., clang-cl -Xclang -fopenmp ... or clang-cl /clang:-fopenmp ... (Which is equivalent of -Xclang -fopenmp).
Remark
On Windows I use Windows Driver of Clang using clang-cl.
Adding clarity to what the OpenMP libraries actually are, and how to use them on Windows with clang-cl
libomp.dll and libiomp5md.dll ARE THE SAME FILES!
When compiling for Windows, you link against libomp.lib OR libiomp5md.lib which will link to the same-named DLL at runtime, i.e. libomp.dll OR libiomp5md.dll respectively.
If you load 2 files that use the "different-name DLL," the interpreter will crash and give you a nasty error like: OMP: Error #15: Initializing libiomp5md.dll, but found libomp.dll already initialized.
Why? Because the program has no idea they are the same DLL, they have different names, so it assumes they are different. And it crashes. For this reason only, you can choose to swap which OpenMP DLL you link to in your program.
If your program doesn't crash and give you an error, you can keep using the same link to OpenMP. Otherwise, to silence the error, link to the one that is loaded by another program already.
If using clang-cl.exe which is the "drop-in" Clang replacement for MSVC cl.exe you should pass a compiler argument such as -Xclang -fopenmp which will convert the argument over to "Clang language." Don't forget to still pass to the linker the OpenMP LIB you chose, because on Windows, it won't be automatic.
That's all I've learned as brief as possible about OpenMP linking on Windows.
To compile and link OpenMP code with clang on Windows, you will have to pass -fopenmp to both the compiler and the linker:
clang -fopenmp -o bla.obj -c bla.c
clang -fopenmp -o bla.exe bla.obj
I have been tweaking GCC 6.3.0 to get it to use the libc++ runtime instead of libstdc++ so that g++ can be used without worrying about C++ runtime incompatibilities:
https://github.com/RJVB/macstrop/tree/master/lang/gcc6
The tweak works, I can build and run KDE software using g++ against Qt5 and KF5 frameworks (and everything else) built with various clang versions.
What doesn't work is generating code that uses AVX and presumably most or all newer intrinsic instructions.
This is not a new issue that's never been invoked on here; it's answered here for instance: How to use AVX/pclmulqdq on Mac OS X
Evidently one can configure gcc to call the linked script instead of the actual as executable.
But can gcc not be configured to use another assembler altogether, like nasm, and would that solve this issue?
I'd like translate my c codes to mips assembly using llvm. How can i do it? I'm on Mac. So llc command does not work.
Thanks
The clang on your MacOS system won't compile for mips by default, you'll need to build your own.
You can look here: http://llvm.org/docs/GettingStarted.html for directions on building up llvm.
After that you can use clang to compile C to mips assembly by doing something like:
clang -target mipsel-linux-gnu foo.c -S -o -
which will compile the file "foo.c" to 32-bit mips assembly for the linux operating system and output it to the console.
I've been trying to build Python from source on my mac with the Intel compiler suite (Intel Parallel Studio) and link it against Intel's MKL.
The reason for that is that I want to use the exactly the same environment on my mac for developing Python code as on our linux cluster.
As long as I am not telling the configure script to use Intel's parallel studio, Python builds fine (configure and make: ./configure --with(out)-gcc). But as soon as I include --with-icc, or if I set the appropriate environment variables, mentioned in ./configure --help, to the Intel compilers and linkers, make fails with:
icc -c -fno-strict-aliasing -fp-model strict -g -O2 -DNDEBUG -g -O3 -Wall -Wstrict-prototypes -I. -IInclude -I./Include -DPy_BUILD_CORE -o Python/getcompiler.o Python/getcompiler.c
Python/getcompiler.c(27): error: expected a ";"
return COMPILER;
^
compilation aborted for Python/getcompiler.c (code 2)
make: *** [Python/getcompiler.o] Error 2
I've searched everywhere, but nobody seems to be interested in building Python on a mac with intel compilers, or I am the only one who has problems with it. I've also configured my environment according to Intel's instructions: source /opt/intel/bin/compilervars.sh intel64, in ~/.bash_profile.
In any case, my environment is:
OS X 10.11.6
Xcode 8.1 / Build version 8B62
Intel Parallel Studio XE 2017.0.036 (C/C++, Fortran)
Thanks,
François
You could edit the line in getcompiler.c that it is complaining about:
e.g. to
return "[Intel compiler]";
If you wanted to get fancier you could add in the compiler version, using e.g. the __INTEL_COMPILER macro.
I know that to compile to assembly, I should use the -Soption with gcc or g++, but how do I get MIPS assembly?
I tried
g++ -march=mips2 dll.c
but that gives the error
dll.c:1:0: error: bad value (mips2) for -march= switch
I saw a suggestion of the compile command mips_gcc, but I can't find how to install that compiler.
I'm using Ubuntu 64-bit, if that helps.
You need a version of gcc that is built as a MIPS cross compiler. You can download the free Mentor/Codesourcery MIPS gnu/gcc cross compilation tool chain from here. This toolchain is available for both Windows and Linux.
After downloading, installing and adding the tool chain to your path you would say:
mips-linux-gnu-g++ -march=mips32r2 -S dll.c
to compile your code to MIPS32R2 assembly.
UPDATE 8/2017:
It looks like Sourcery CodeBench free cross compiler for MIPS is no longer available at Mentor's site.
Try the free toolchain at Imagination's site.