`v4l2tools`: Includes buildhost's header file and fails to build with `/usr/include/bits/floatn.h:86:9: error: '__float128' does not name a type; did you mean '__cfloat128'?`.

[dreirund]

Ahoj,

when I try to build v4l2tools from the HandsomeMod/handsomefeed feed, it fails while building v4l2wrapper with
/usr/include/bits/floatn.h:86:9: error: '__float128' does not name a type; did you mean '__cfloat128'?
and many subsequent errors.

It is including stuff from the buildhost's filesystem instead of cross-compiled stuff.

I am building for Qualcomm msm8916.

After a failing make -j6, here the terminal output of
make -j1 V=sc package/feeds/handsomefeed/v4l2tools/compile:

[...]
make[3]: Entering directory '/[...]/build_dir/target-aarch64_cortex-a53+neon_musl/v4l2tools-20200531/v4l2wrapper'
aarch64-openwrt-linux-musl-g++ -c -o src/V4l2Access.o src/V4l2Access.cpp -W -pthread -g -pipe  -I inc -DHAVE_LOG4CPP -I /usr/include
In file included from /usr/include/wchar.h:30,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cwchar:44,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/postypes.h:40,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/char_traits.h:40,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:40,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/usr/include/bits/floatn.h:86:9: error: '__float128' does not name a type; did you mean '__cfloat128'?
 typedef __float128 _Float128;
         ^~~~~~~~~~
         __cfloat128
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cwchar:44,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/postypes.h:40,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/char_traits.h:40,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:40,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/usr/include/wchar.h:407:8: error: '_Float128' does not name a type; did you mean '_Float32x'?
 extern _Float128 wcstof128 (const wchar_t *__restrict __nptr,
        ^~~~~~~~~
        _Float32x
/usr/include/wchar.h:524:8: error: '_Float128' does not name a type; did you mean '_Float32x'?
 extern _Float128 wcstof128_l (const wchar_t *__restrict __nptr,
        ^~~~~~~~~
        _Float32x
/usr/include/wchar.h:615:9: error: '__gnuc_va_list' has not been declared
         __gnuc_va_list __arg)
         ^~~~~~~~~~~~~~
/usr/include/wchar.h:622:8: error: '__gnuc_va_list' has not been declared
        __gnuc_va_list __arg)
        ^~~~~~~~~~~~~~
/usr/include/wchar.h:628:9: error: '__gnuc_va_list' has not been declared
         __gnuc_va_list __arg)
         ^~~~~~~~~~~~~~
/usr/include/wchar.h:690:8: error: '__gnuc_va_list' has not been declared
        __gnuc_va_list __arg)
        ^~~~~~~~~~~~~~
/usr/include/wchar.h:697:7: error: '__gnuc_va_list' has not been declared
       __gnuc_va_list __arg)
       ^~~~~~~~~~~~~~
/usr/include/wchar.h:702:8: error: '__gnuc_va_list' has not been declared
        __gnuc_va_list __arg)
        ^~~~~~~~~~~~~~
In file included from /usr/include/features.h:490,
                 from /usr/include/bits/libc-header-start.h:33,
                 from /usr/include/wchar.h:27,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cwchar:44,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/postypes.h:40,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/char_traits.h:40,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:40,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/usr/include/wchar.h:711:12: error: '__gnuc_va_list' has not been declared
 extern int __REDIRECT (vfwscanf, (__FILE *__restrict __s,
            ^~~~~~~~~~
/usr/include/wchar.h:715:12: error: '__gnuc_va_list' has not been declared
 extern int __REDIRECT (vwscanf, (const wchar_t *__restrict __format,
            ^~~~~~~~~~
/usr/include/wchar.h:718:12: error: '__gnuc_va_list' has not been declared
 extern int __REDIRECT_NTH (vswscanf, (const wchar_t *__restrict __s,
            ^~~~~~~~~~~~~~
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cstdlib:75,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:41,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/include/stdlib.h:44:1: error: '_Noreturn' does not name a type
 _Noreturn void abort (void);
 ^~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/include/stdlib.h:46:1: error: '_Noreturn' does not name a type
 _Noreturn void exit (int);
 ^~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/include/stdlib.h:47:1: error: '_Noreturn' does not name a type
 _Noreturn void _Exit (int);
 ^~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/include/stdlib.h:49:1: error: '_Noreturn' does not name a type
 _Noreturn void quick_exit (int);
 ^~~~~~~~~
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:41,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cstdlib:130:11: error: '::abort' has not been declared
   using ::abort;
           ^~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cstdlib:146:11: error: '::exit' has not been declared
   using ::exit;
           ^~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cstdlib:160:11: error: '::quick_exit' has not been declared
   using ::quick_exit;
           ^~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cstdlib:206:11: error: '::_Exit' has not been declared
   using ::_Exit;
           ^~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cstdlib:242:22: error: '__gnu_cxx::_Exit' has not been declared
   using ::__gnu_cxx::_Exit;
                      ^~~~~
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cstdio:42,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:43,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/usr/include/stdio.h:52:9: error: '__gnuc_va_list' does not name a type; did you mean 'va_list'?
 typedef __gnuc_va_list va_list;
         ^~~~~~~~~~~~~~
         va_list
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cstdio:42,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:43,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/usr/include/stdio.h:366:8: error: '__gnuc_va_list' has not been declared
        __gnuc_va_list __arg);
        ^~~~~~~~~~~~~~
/usr/include/stdio.h:371:54: error: '__gnuc_va_list' has not been declared
 extern int vprintf (const char *__restrict __format, __gnuc_va_list __arg);
                                                      ^~~~~~~~~~~~~~
/usr/include/stdio.h:374:8: error: '__gnuc_va_list' has not been declared
        __gnuc_va_list __arg) __THROWNL;
        ^~~~~~~~~~~~~~
/usr/include/stdio.h:383:42: error: '__gnuc_va_list' has not been declared
         const char *__restrict __format, __gnuc_va_list __arg)
                                          ^~~~~~~~~~~~~~
/usr/include/stdio.h:391:9: error: '__gnuc_va_list' has not been declared
         __gnuc_va_list __arg)
         ^~~~~~~~~~~~~~
/usr/include/stdio.h:404:8: error: '__gnuc_va_list' has not been declared
        __gnuc_va_list __arg)
        ^~~~~~~~~~~~~~
/usr/include/stdio.h:460:7: error: '__gnuc_va_list' has not been declared
       __gnuc_va_list __arg)
       ^~~~~~~~~~~~~~
/usr/include/stdio.h:467:53: error: '__gnuc_va_list' has not been declared
 extern int vscanf (const char *__restrict __format, __gnuc_va_list __arg)
                                                     ^~~~~~~~~~~~~~
/usr/include/stdio.h:472:40: error: '__gnuc_va_list' has not been declared
       const char *__restrict __format, __gnuc_va_list __arg)
                                        ^~~~~~~~~~~~~~
In file included from /usr/include/features.h:490,
                 from /usr/include/bits/libc-header-start.h:33,
                 from /usr/include/wchar.h:27,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cwchar:44,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/postypes.h:40,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/char_traits.h:40,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:40,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/usr/include/stdio.h:479:12: error: '__gnuc_va_list' has not been declared
 extern int __REDIRECT (vfscanf,
            ^~~~~~~~~~
/usr/include/stdio.h:484:12: error: '__gnuc_va_list' has not been declared
 extern int __REDIRECT (vscanf, (const char *__restrict __format,
            ^~~~~~~~~~
/usr/include/stdio.h:487:12: error: '__gnuc_va_list' has not been declared
 extern int __REDIRECT_NTH (vsscanf,
            ^~~~~~~~~~~~~~
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/cstdio:42,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:43,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/usr/include/stdio.h:858:8: error: '__gnuc_va_list' has not been declared
        __gnuc_va_list __args)
        ^~~~~~~~~~~~~~
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::string std::to_string(int)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6455:20: error: no matching function for call to '__to_xstring<std::string>(int (*)(char*, size_t, const char*, int) noexcept, long unsigned int, const char [3], int&)'
         "%d", __val); }
                    ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6455:20: note:   mismatched types '__va_list' and 'int'
         "%d", __val); }
                    ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::string std::to_string(unsigned int)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6461:20: error: no matching function for call to '__to_xstring<std::string>(int (*)(char*, size_t, const char*, int) noexcept, long unsigned int, const char [3], unsigned int&)'
         "%u", __val); }
                    ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6461:20: note:   mismatched types '__va_list' and 'int'
         "%u", __val); }
                    ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::string std::to_string(long int)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6466:21: error: no matching function for call to '__to_xstring<std::string>(int (*)(char*, size_t, const char*, int) noexcept, long unsigned int, const char [4], long int&)'
         "%ld", __val); }
                     ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6466:21: note:   mismatched types '__va_list' and 'int'
         "%ld", __val); }
                     ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::string std::to_string(long unsigned int)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6472:21: error: no matching function for call to '__to_xstring<std::string>(int (*)(char*, size_t, const char*, int) noexcept, long unsigned int, const char [4], long unsigned int&)'
         "%lu", __val); }
                     ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6472:21: note:   mismatched types '__va_list' and 'int'
         "%lu", __val); }
                     ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::string std::to_string(long long int)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6478:22: error: no matching function for call to '__to_xstring<std::string>(int (*)(char*, size_t, const char*, int) noexcept, long unsigned int, const char [5], long long int&)'
         "%lld", __val); }
                      ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6478:22: note:   mismatched types '__va_list' and 'int'
         "%lld", __val); }
                      ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::string std::to_string(long long unsigned int)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6484:22: error: no matching function for call to '__to_xstring<std::string>(int (*)(char*, size_t, const char*, int) noexcept, long unsigned int, const char [5], long long unsigned int&)'
         "%llu", __val); }
                      ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6484:22: note:   mismatched types '__va_list' and 'int'
         "%llu", __val); }
                      ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::string std::to_string(float)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6492:20: error: no matching function for call to '__to_xstring<std::string>(int (*)(char*, size_t, const char*, int) noexcept, const int&, const char [3], float&)'
         "%f", __val);
                    ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6492:20: note:   mismatched types '__va_list' and 'int'
         "%f", __val);
                    ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::string std::to_string(double)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6501:20: error: no matching function for call to '__to_xstring<std::string>(int (*)(char*, size_t, const char*, int) noexcept, const int&, const char [3], double&)'
         "%f", __val);
                    ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6501:20: note:   mismatched types '__va_list' and 'int'
         "%f", __val);
                    ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::string std::to_string(long double)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6510:21: error: no matching function for call to '__to_xstring<std::string>(int (*)(char*, size_t, const char*, int) noexcept, const int&, const char [4], long double&)'
         "%Lf", __val);
                     ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6510:21: note:   mismatched types '__va_list' and 'int'
         "%Lf", __val);
                     ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::wstring std::to_wstring(int)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6558:22: error: no matching function for call to '__to_xstring<std::wstring>(int (*)(wchar_t*, size_t, const wchar_t*, int) noexcept, long unsigned int, const wchar_t [3], int&)'
          L"%d", __val); }
                      ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6558:22: note:   mismatched types '__va_list' and 'int'
          L"%d", __val); }
                      ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::wstring std::to_wstring(unsigned int)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6564:22: error: no matching function for call to '__to_xstring<std::wstring>(int (*)(wchar_t*, size_t, const wchar_t*, int) noexcept, long unsigned int, const wchar_t [3], unsigned int&)'
          L"%u", __val); }
                      ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6564:22: note:   mismatched types '__va_list' and 'int'
          L"%u", __val); }
                      ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::wstring std::to_wstring(long int)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6569:23: error: no matching function for call to '__to_xstring<std::wstring>(int (*)(wchar_t*, size_t, const wchar_t*, int) noexcept, long unsigned int, const wchar_t [4], long int&)'
          L"%ld", __val); }
                       ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6569:23: note:   mismatched types '__va_list' and 'int'
          L"%ld", __val); }
                       ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::wstring std::to_wstring(long unsigned int)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6575:23: error: no matching function for call to '__to_xstring<std::wstring>(int (*)(wchar_t*, size_t, const wchar_t*, int) noexcept, long unsigned int, const wchar_t [4], long unsigned int&)'
          L"%lu", __val); }
                       ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6575:23: note:   mismatched types '__va_list' and 'int'
          L"%lu", __val); }
                       ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::wstring std::to_wstring(long long int)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6581:24: error: no matching function for call to '__to_xstring<std::wstring>(int (*)(wchar_t*, size_t, const wchar_t*, int) noexcept, long unsigned int, const wchar_t [5], long long int&)'
          L"%lld", __val); }
                        ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6581:24: note:   mismatched types '__va_list' and 'int'
          L"%lld", __val); }
                        ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::wstring std::to_wstring(long long unsigned int)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6587:24: error: no matching function for call to '__to_xstring<std::wstring>(int (*)(wchar_t*, size_t, const wchar_t*, int) noexcept, long unsigned int, const wchar_t [5], long long unsigned int&)'
          L"%llu", __val); }
                        ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6587:24: note:   mismatched types '__va_list' and 'int'
          L"%llu", __val); }
                        ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::wstring std::to_wstring(float)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6595:22: error: no matching function for call to '__to_xstring<std::wstring>(int (*)(wchar_t*, size_t, const wchar_t*, int) noexcept, const int&, const wchar_t [3], float&)'
          L"%f", __val);
                      ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6595:22: note:   mismatched types '__va_list' and 'int'
          L"%f", __val);
                      ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::wstring std::to_wstring(double)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6604:22: error: no matching function for call to '__to_xstring<std::wstring>(int (*)(wchar_t*, size_t, const wchar_t*, int) noexcept, const int&, const wchar_t [3], double&)'
          L"%f", __val);
                      ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6604:22: note:   mismatched types '__va_list' and 'int'
          L"%f", __val);
                      ^
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h: In function 'std::wstring std::to_wstring(long double)':
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6613:23: error: no matching function for call to '__to_xstring<std::wstring>(int (*)(wchar_t*, size_t, const wchar_t*, int) noexcept, const int&, const wchar_t [4], long double&)'
          L"%Lf", __val);
                       ^
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6400,
                 from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note: candidate: 'template<class _String, class _CharT> _String __gnu_cxx::__to_xstring(int (*)(_CharT*, std::size_t, const _CharT*, __va_list), std::size_t, const _CharT*, ...)'
     __to_xstring(int (*__convf) (_CharT*, std::size_t, const _CharT*,
     ^~~~~~~~~~~~
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/ext/string_conversions.h:99:5: note:   template argument deduction/substitution failed:
In file included from /[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/string:52,
                 from inc/V4l2Device.h:16,
                 from inc/V4l2Access.h:16,
                 from src/V4l2Access.cpp:12:
/[...]/staging_dir/toolchain-aarch64_cortex-a53+neon_gcc-8.4.0_musl/aarch64-openwrt-linux-musl/include/c++/8.4.0/bits/basic_string.h:6613:23: note:   mismatched types '__va_list' and 'int'
          L"%Lf", __val);
                       ^
make[3]: *** [Makefile:20: src/V4l2Access.o] Error 1
make[3]: Leaving directory '/[...]/build_dir/target-aarch64_cortex-a53+neon_musl/v4l2tools-20200531/v4l2wrapper'
[...]

Interesting that it wants to include stuff from /usr/include/bits/, which is on the buildhost's filesystem. Instead, it should include stuff from the local, cross-compiled, directory structure.

→ Full package build terminal output.

Configuration:

• grep -i v4l .config:

  CONFIG_EUDEV_EXTRA_v4l_id=y
  # CONFIG_PACKAGE_kmod-video-v4l2loopback is not set
  CONFIG_PACKAGE_libv4l=m
  CONFIG_MJPG_STREAMER_V4L2=y
  # CONFIG_PACKAGE_v4l2rtspserver is not set
  CONFIG_PACKAGE_v4l2tools=m
  CONFIG_PACKAGE_v4l-utils=m
  

• → Full .config.