Make error: bits/c++config.h: No such file or directory

[gerwang]

I am using anaconda's gcc_linux-64 with no multilib support. When I execute make I get

.../include/c++/7.3.0/complex.h:29:10: fatal error: bits/c++config.h: No such file or directory #include <bits/c++config.h>

which is invoked in file common.h:

520       (__GNUC__ >= 3 && !defined(__cplusplus))) && !(defined(FORCE_OPENBLAS_COMPLEX_STRUCT))) && !defined(_MSC_VER)
521   #define OPENBLAS_COMPLEX_C99
522   #ifndef __cplusplus
523     #include <complex.h> // here
524   #endif

Yes, there is no c++config.h in .../include/c++/7.3.0/. But when I compile a small test program:

#include <complex>
#include <iostream>
using namespace std;

complex<double> nmb;

int main() {
        std::cout<<nmb.real()<<" "<<nmb.imag()<<std::endl;
}

It compiles and works.

[isuruf]

You need to post a more detailed error log

[gerwang]

Thanks for reply.

Here is the stderr of my make: https://gist.github.com/gerwang/0ecd264cff529588b769883aa0fe6ba2

By the way, I am using Intel(R) Xeon(R) CPU E5-2660 v3, a haswell cpu.

[isuruf]

Need the stdout too

[martin-frbg]

On my (SuSE) system, this is part of the libstdc++-devel package

[gerwang]

Updated https://gist.github.com/gerwang/0ecd264cff529588b769883aa0fe6ba2

[isuruf]

See #818 (comment)

You might need to unset CFLAGS and set them using make. See https://github.com/conda-forge/openblas-feedstock/blob/master/recipe/build.sh

[martin-frbg]

I do not believe the macro redefinition warning (issue #818) is anything more than a harmless nuisance caused by the somewhat recursive Makefile structure. Note that it is one of the gcc headers itself (complex.h) that is failing to find c++config.h - what does this file contain on your system ? (On mine, both the complex.h and plain "complex" there expect to include the c++config.h) Are you perhaps trying to cross-compile OpenBLAS on that system without having the appropriate multilib package installed (e.g. https://stackoverflow.com/questions/34437483/bits-cconfig-h-no-such-file-or-directory/36556287#36556287 ) ?

[isuruf]

conda compiler has a custom sysroot and doesn't look at the files in the system. @gerwang, do you have CPLUS_INCLUDE_PATH or similar env variable set?

[gerwang]

Thanks, solved my problem.

[martin-frbg]

@gerwang could you please tell what the solution was ?

[gerwang]

Yes, by changing my gcc to the one supports multilib.
Since I don't have sudo privilege, I use linuxbrew's gcc, which I can find c++config.h from ~/.linuxbrew/include/c++/5.5.0/x86_64-unknown-linux-gnu/bits.

I searched through conda's repo can didn't find conda's multilib gcc, so I gave up using conda's gcc.

So I wonder, does OpenBLAS requires multilib gcc to build? I am not going to cross compiling OpenBLAS, just want to use it on the build machine.

[isuruf]

@gerwang, did you have CPLUS_INCLUDE_PATH set?

[gerwang]

I think a simple solution to use on gcc with no multilib is to disable C99's complex support, reverts to using OpenBLAS's custom complex structure. Once I tried to refactor common.h to stop using C99's complex.h, but I found out there are many direct includes to complex.h, so finally I gave up. Maybe there can be an option to disable complex.h on compiler that is not multilib.