sqrt(int_value + 0.0) -- Does it have a purpose?
- by Earlz
Hello, while doing some homework in my very strange C++ book, which I've been told before to throw away, had a very peculiar code segment. I know homework stuff always throws in extra "mystery" to try to confuse you like indenting 2 lines after a single-statement for-loop. But this one I'm confused on because it seems to serve some real-purpose.
basically it is like this:
int counter=10;
...
if(pow(floor(sqrt(counter+0.0)),2) == counter)
...
I'm interested in this part especially:
sqrt(counter+0.0)
Is there some purpose to the +0.0? Is this the poormans way of doing a static cast to a double? Does this avoid some compiler warning on some compiler I do not use? The entire program printed the exact same thing and compiled without warnings on g++ whenever I left out the +0.0 part. Maybe I'm not using a weird enough compiler?
Edit:
Also, does gcc just break standard and not make an error for Ambiguous reference since sqrt can take 3 different types of parameters?
[earlz@EarlzBeta-~/projects/homework1] $ cat calc.cpp
#include <cmath>
int main(){
int counter=0;
sqrt(counter);
}
[earlz@EarlzBeta-~/projects/homework1] $ g++ calc.cpp
/usr/lib/libstdc++.so.47.0: warning: strcpy() is almost always misused, please use strlcpy()
/usr/lib/libstdc++.so.47.0: warning: strcat() is almost always misused, please use strlcat()
[earlz@EarlzBeta-~/projects/homework1] $
