error: inlining failed in call to always_inline ‘long long int _mm_popcnt_u64(long long unsigned int)’: target specific option mismatch

[ckorn]

Hi,

on Ubuntu 17.04 there is this compilation error:

g++ -g -O2 -fdebug-prefix-map=/home/korn/packages/mve/mve-0.0.0+git20170629=. -fstack-protector-strong -Wformat -Werror=format-security -pthread -I../../libs -fopenmp -Wdate-time -D_FORTIFY_SOURCE=2 -c -o pose_p3p.o pose_p3p.cc
In file included from ../../libs/sfm/cascade_hashing.h:20:0,
                 from cascade_hashing.cc:14:
/usr/lib/gcc/x86_64-linux-gnu/6/include/popcntintrin.h: In member function ‘void sfm::CascadeHashing::collect_features_from_buckets(std::vector<std::vector<unsigned int> >*, size_t, std::vector<bool>*, const BucketGroupsBuckets&, const BucketGroupsFeatures&, const uint64_t*, const std::vector<long unsigned int, std::allocator<long unsigned int> >&) const [with int DIMHASH = 128]’:
/usr/lib/gcc/x86_64-linux-gnu/6/include/popcntintrin.h:42:1: error: inlining failed in call to always_inline ‘long long int _mm_popcnt_u64(long long unsigned int)’: target specific option mismatch
 _mm_popcnt_u64 (unsigned long long __X)
 ^~~~~~~~~~~~~~
In file included from cascade_hashing.cc:14:0:
../../libs/sfm/cascade_hashing.h:452:47: note: called from here
                 hamming_dist += _mm_popcnt_u64(comp_hash_data1[k] ^ ptr2[k]);
                                 ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ../../libs/sfm/cascade_hashing.h:20:0,
                 from cascade_hashing.cc:14:
/usr/lib/gcc/x86_64-linux-gnu/6/include/popcntintrin.h:42:1: error: inlining failed in call to always_inline ‘long long int _mm_popcnt_u64(long long unsigned int)’: target specific option mismatch

[flanggut]

The compile command doesn't activate the popcount intrinsic. What build system do you use?

[ckorn]

This is with the make build system.

Here, should have provided the entire build log.
build_log.txt

[flanggut]

If you use the Makefile provided by MVE this should be the compiler call:

g++ -Wall -Wextra -Wundef -pedantic -msse2 -msse3 -mpopcnt -funsafe-math-optimizations -fno-math-errno -std=c++11 -g -O3 -pthread -I../../libs   -c -o cascade_hashing.o cascade_hashing.cc

There's definitely something wrong with your build system.

[simonfuhrmann]

Are you compiling on a 32 bit system? What does uname -m say?

[HelliceSaouli]

Out of topic but Ubuntu 17.04 is not LTS and it will never be stable thus you will straggle using it a specially if you are working on computer graphics and vision problem ( lack of good gpu drivers) i suggest you use 14.04 LTS so stable version of Ubuntu

[ckorn]

Ok, seems the build system has overridden the defaults in Makefile.inc. Had to apply this patch to make it work:
http://sprunge.us/jMfg

Thanks for your hints.

Now the build succeeds on amd64. But there is this build error now on i386:

../../libs/sfm/cascade_hashing.h:452:47: error: ‘_mm_popcnt_u64’ was not declared in this scope

Could you please have a look? Here is the build log:
build_log.txt

[simonfuhrmann]

@andre-schulz

[flanggut]

just a guess but this is the only thing I could find: _mm_popcnt_u64 is only available on 64bit systems. how old is your machine?

[andre-schulz]

As @flanggut guessed correctly, _mm_popcnt_u64() is only available when compiling a 64-bit binary (see popcntintrin.h). AFAIK, compiling MVE in 32-bit mode is not supported. Is that correct, @simonfuhrmann?

[simonfuhrmann]

It was never explicitly unsupported, as we were not aware that it doesn't compile on 32 bit anymore. But using it on a 32 bit system is somewhat useless, since it allows you to make use of 4 GB of memory only. Which is usually not enough. It would be nice if we could replace (or ifdef) this function to make it work on 32 bit machines, but if it's not possible, it's not the worst thing in the world to drop 32 bit support.

[simonfuhrmann]

@andre-schulz, can we make this work on 32 bit machines?

[andre-schulz]

Yes, I just have to find a way to do this cleanly.

[LinusVanElswijk]

You could use std::bitset::count. It should automatically use the best popcount instruction available.

/** Returns the number of one bits of an integer. */
template <typename T>
inline std::size_t
popcount (T const& x)
{
    static_assert(std::is_integral<T>::value, "T must be an integral type.");
    const std::bitset<sizeof(T) * 8> bits(x);
    return bits.count();
}

You can explore resulting binaries here: https://godbolt.org/g/McZWwU