Invalid convertion in int main function

[vasilikisdr]

While installing the sar_tools I get that dateconv.cc: In function ‘int main(int, char*)’: error: invalid conversion from ‘char’ to ‘size_t’ {aka ‘long unsigned int’} [-fpermissive] 51	strftime(indatestring,informat,&tm_tmp);	^~~~
char*

dateconv.cc:51:34: error: cannot convert ‘tm’ to ‘const char’ 51	strftime(indatestring,informat,&tm_tmp);	^~~
tm*

In file included from /usr/include/pthread.h:14, from /usr/lib/gcc/x86_64-pc-cygwin/9.3.0/include/c++/x86_64-pc-cygwin/bits/gthr-default.h:35, from /usr/lib/gcc/x86_64-pc-cygwin/9.3.0/include/c++/x86_64-pc-cygwin/bits/gthr.h:148, from /usr/lib/gcc/x86_64-pc-cygwin/9.3.0/include/c++/ext/atomicity.h:35, from /usr/lib/gcc/x86_64-pc-cygwin/9.3.0/include/c++/bits/ios_base.h:39, from /usr/lib/gcc/x86_64-pc-cygwin/9.3.0/include/c++/ios:42, from /usr/lib/gcc/x86_64-pc-cygwin/9.3.0/include/c++/ostream:38, from /usr/lib/gcc/x86_64-pc-cygwin/9.3.0/include/c++/iostream:39, from dateconv.cc:9: /usr/include/time.h:67:49: note: initializing argument 3 of ‘size_t strftime(char, size_t, const char, const tm)’ 67 | size_t _maxsize, const char __restrict _fmt, | ~~~~~^~ make: *** [: dateconv.o] Error 1

and it doesn't run the make command for the sar_tools. Does anyone know how to fix it?