Andreas Tille <andr...@an3as.eu> wrote: > Hi, > > to fix bug #853568 I tried a patch (gcc-7.patch) to fix abs() arguments > in nanopolish[1] but I have no idea how to deal with this: > > ... > g++ -o src/hmm/nanopolish_pore_model_set.o -c -g -O2 > -fdebug-prefix-map=/build/nanopolish-0.5.0=. -fstack-protector-strong > -Wformat -Werror=format-security -g -O3 -std=c++11 -fopenmp -Wdate-t > src/common/nanopolish_variant.cpp: In function 'std::vector<Variant> > extract_variants(const string&, const string&)': > src/common/nanopolish_variant.cpp:32:69: error: call of overloaded > 'abs(std::__cxx11::basic_string<char>::size_type)' is ambiguous > size_t difference = std::abs(reference.size() - haplotype.size());
The result of subtracting two size_t's is still a size_t, which is unsigned. So you need to cast it to a signed type. The correct type is ptrdiff_t. http://en.cppreference.com/w/cpp/types/ptrdiff_t The line then becomes size_t difference = std::abs(static_cast<ptrdiff_t>(reference.size() - haplotype.size())); Or you could do it in two lines ptrdiff_t diff_signed (reference.size() - haplotype.size()); size_t difference = std::abs(diff_signed); Cheers, Walter Landry
