absl/time/internal/cctz/src/time_zone_format.cc:28
  ../src/absl/time/internal/cctz/include/cctz/time_zone.h:26
/usr/include/g++/string:40
/usr/include/g++/bits/char_traits.h:40
/usr/include/g++/bits/postypes.h:40:0
/usr/include/g++/cwchar:164:11:

view /usr/pkg/gcc12/include/c++/cwchar

    133 #if _GLIBCXX_USE_WCHAR_T
    134
    135 extern "C++"
    136 {
    137 namespace std _GLIBCXX_VISIBILITY(default)
    138 {
    139 _GLIBCXX_BEGIN_NAMESPACE_VERSION
    140
    141   using ::wint_t;
    142
    143   using ::btowc;
    144   using ::fgetwc;
    145   using ::fgetws;
    146   using ::fputwc;
    147   using ::fputws;
    148   using ::fwide;
    149   using ::fwprintf;
    150   using ::fwscanf;
    151   using ::getwc;
    152   using ::getwchar;
    153   using ::mbrlen;
    154   using ::mbrtowc;
    155   using ::mbsinit;
    156   using ::mbsrtowcs;
    157   using ::putwc;
    158   using ::putwchar;
    159 #ifndef _GLIBCXX_HAVE_BROKEN_VSWPRINTF
    160   using ::swprintf;
    161 #endif
    162   using ::swscanf;
    163   using ::ungetwc;
    164   using ::vfwprintf;

grep -nr vfwprintf /usr/pkg/gcc12

/usr/pkg/gcc12/lib/gcc/x86_64--netbsd/12.4.0/include-fixed/wchar.h:200:
   int vfwprintf(FILE * __restrict, const wchar_t * __restrict, __gnuc_va_list);
/usr/pkg/gcc12/lib/gcc/x86_64--netbsd/12.4.0/include-fixed/wchar.h:293:
   int vfwprintf_l(FILE * __restrict, locale_t,

view /usr/pkg/gcc12/lib/gcc/x86_64--netbsd/12.4.0/include-fixed/wchar.h

    271 #if defined(_NETBSD_SOURCE)
    272 __BEGIN_DECLS
      ...
    293 int vfwprintf_l(FILE * __restrict, locale_t,

thinkc-01@makoto 21:34:11/250102(~)% find /usr/pkg/gcc*/lib -name wchar.h -ls

2627551 28 -rw-r--r-- 1 root  wheel 12403 Jun 12  2024 /usr/pkg/gcc10-aux/lib/gcc/x86_64--netbsd/10.3.0/include-fixed/wchar.h
1417436 28 -rw-r--r-- 1 root  wheel 12403 Apr 27  2024 /usr/pkg/gcc10/lib/gcc/x86_64--netbsd/10.5.0/include-fixed/wchar.h
2331438 28 -rw-r--r-- 1 root  wheel 12403 Dec 11 23:27 /usr/pkg/gcc12/lib/gcc/x86_64--netbsd/12.4.0/include-fixed/wchar.h
2017321 28 -rw-r--r-- 1 root  wheel 12403 Dec 23 21:03 /usr/pkg/gcc14/lib/gcc/x86_64--netbsd/14.2.0/include-fixed/wchar.h
1370925 28 -rw-r--r-- 1 root  wheel 12403 Jun 11  2024 /usr/pkg/gcc7/lib/gcc/x86_64--netbsd/7.5.0/include-fixed/wchar.h
1920088 28 -rw-r--r-- 1 root  wheel 12403 Jun 11  2024 /usr/pkg/gcc8/lib/gcc/x86_64--netbsd/8.5.0/include-fixed/wchar.h

thinkc-01@makoto 21:34:34/250102(~)% md5 `find /usr/pkg/gcc*/lib -name wchar.h `

MD5 (/usr/pkg/gcc10-aux/lib/gcc/x86_64--netbsd/10.3.0/include-fixed/wchar.h) = afa3530e872d97f0012f9214a5314573
MD5 (/usr/pkg/gcc10/lib/gcc/x86_64--netbsd/10.5.0/include-fixed/wchar.h) = afa3530e872d97f0012f9214a5314573
MD5 (/usr/pkg/gcc12/lib/gcc/x86_64--netbsd/12.4.0/include-fixed/wchar.h) = afa3530e872d97f0012f9214a5314573
MD5 (/usr/pkg/gcc14/lib/gcc/x86_64--netbsd/14.2.0/include-fixed/wchar.h) = afa3530e872d97f0012f9214a5314573
MD5 (/usr/pkg/gcc7/lib/gcc/x86_64--netbsd/7.5.0/include-fixed/wchar.h) = afa3530e872d97f0012f9214a5314573
MD5 (/usr/pkg/gcc8/lib/gcc/x86_64--netbsd/8.5.0/include-fixed/wchar.h) = afa3530e872d97f0012f9214a5314573
thinkc-01@makoto 21:34:41/250102(~)%

Files are all the same.