/tmp/tmp853.c: In function ‘main’:
/tmp/tmp853.c:4:20: error: ‘__int64’ undeclared (first use in this function)
    4 |         if (sizeof(__int64)==8) return 0;
      |                    ^~~~~~~
/tmp/tmp853.c:4:20: note: each undeclared identifier is reported only once for each function it appears in
/tmp/tmp853.c: In function ‘main’:
/tmp/tmp853.c:5:9: warning: ignoring return value of ‘strdup’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
    5 |         strdup("str");
      |         ^~~~~~~~~~~~~
/tmp/tmp853.c: In function ‘main’:
/tmp/tmp853.c:5:9: warning: implicit declaration of function ‘_strdup’; did you mean ‘strdup’? [-Wimplicit-function-declaration]
    5 |         _strdup("str");
      |         ^~~~~~~
      |         strdup
/usr/bin/ld: /tmp/ccTWSte4.o: in function `main':
tmp853.c:(.text+0x1a): undefined reference to `_strdup'
collect2: error: ld returned 1 exit status
Potential libraries are '-lm -lpcre':
'-lm' found at /usr/lib/libm.so
'-lpcre' found at /usr/lib/libpcre.so.1.2.12
Please specify prototyping behavior for Pro.xs (see perlxs manual)