gettimeofday() not declared in this scope - Cygwin - c++

Question

Can cygwin make use of gettimeofday()? I'm getting the error:
lab8.cpp: In function ‘int main()’:
lab8.cpp:62:30: error: ‘gettimeofday’ was not declared in this scope
gettimeofday(&start, NULL);
^
makefile:14: recipe for target 'lab8.o' failed
make: *** [lab8.o] Error 1
I definitely included <sys/time.h>. Is there a package that I have to install or does it just not work on Windows?
EDIT: Here's a simple test that yields the same error:
#include <sys/time.h>
int main() {
struct timeval start;
gettimeofday(&start, NULL);
}
With the error:
$ g++ -c -Wall -g -std=c++11 test.cpp -o test.o
test.cpp: In function ‘int main()’:
test.cpp:6:30: error: ‘gettimeofday’ was not declared in this scope
gettimeofday(&start, NULL);

Answer 1

You need to define _BSD_SOURCE to include the declaration gettimeofday (since glibc2.2.2 according to link below)
#define _BSD_SOURCE
#include <sys/time.h>
int main() {
struct timeval start;
gettimeofday(&start, NULL);
}
gettimeofday() - Unix, Linux System Call

Answer 2

Thank you John - your question game me my answer!
In case it helps anyone else searching on this error...
I got the same error:
error: ‘gettimeofday’ was not declared in this scope
gettimeofday(&lastBigTick, NULL);
This error started happening when I moved from Debian 8 (jessie) to Debian 9 (stretch) on a raspberry pi
For me, I had NOT #included "sys/time.h" I had only #included "time.h"
Not sure how it compiled before, but it did, so adding
#include "sys/time.h"
did the job for me.
Note: "time.h" is different and is still needed for other time functions, so I ended up needing both:
#include "time.h"
#include "sys/time.h"
My situation was perhaps different, as adding
#define _BSD_SOURCE
made no difference in my case - ie this was not the issue for me.